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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

9 months ago, I put my entire life savings into the down payment for a
home (built in 1955) in the Oakland Hills (northern california)

My fiancé and I recently found out that our monstrous 50 year old 255K
BTU furnace (70% efficiency in its day) has cracks in 4 out of 6 of
the heat exchangers and was emitting carbon monoxide (yikes!). They
no longer make residential furnaces of that size, so deciding how to
replace it has been an exercise in frustration and confusion. We have
gotten 5 separate estimates, all providing vastly different opinions as
to what should be done to replace our furnace and adequately and most
efficiently heat our home. How is one to know who to trust and
believe? My head is spinning from all of the different advice we've
been given (which I'll detail further down in this post)

To complicate things further, our home was custom built by the previous
owner, and has a very unique open floor plan on the upstairs level,
which constitutes about 2600 sq feet of the home. There are 11
registers and 2 large returns on the upstairs level (although both my
office and our dining room have NO registers and we've been told they
can't be added). The downstairs level accounts for approximately 600
square feet and contains our family room (which has a single register
in it)and a guest bedroom with no registers in it.

The entire length of the house, on both levels, has floor to ceiling
windows facing south that provide a breathtaking panoramic view of the
bay. However, they are older windows, with metal frames, and are very
inefficient -- the house loses a lot of heat when it is cold through
those windows, yet when the sun is out the vast southern exposure beams
through the house, heating it sometimes to the point where I literally
feel like a dog locked in a car on a hot summer day. We are in the
hills, and it can get windy, meaning it can get super cold at night.
Yet when the sun is shining, it actually heats up to the point that by
mid-afternoon I'm opening windows because it's too warm -- even in
November (although once the rainy season starts it will be cold all the
time -- I know this from our first month in the house, last February,
wherein we got a $550 PG&E bill that almost gave me a heart attack...
-- after that I had tried not running the heat, but even with wool
sweaters my fingers were still too cold to type and you can't operate a
touchpad with gloves on..)

We have a home warranty, which should cover the cost of replacing the
furnace, although it turns out that the list of uncovered items is much
larger than what is covered.. The home warranty sent out Company A to
provide an estimate for the furnace replacement. They came back with
the suggestion of replacing our 70% efficient 255K BTU furnace with an
80% 100K BTU furnace to the tune of $6300, $2100 of which we would have
to pay out of pocket. As we were shocked both by the price, and by the
size of the unit they were suggesting (how could this adequately heat
our home?), I did a little researching on the Better Business Bureau
website and found Company A had several unresolved complaints filed
against them. Not good.

I decided to get some estimates of my own, and had 3 separate
companies come out to the house. Companies B & C each suggested
getting a single 80% efficiency 155K BTU unit. However, we were
concerned whether even this would provide adequate heating AND we were
informed both by the home warranty company and by Company E (who
provided estimate number 5 as a 2nd opinion on behalf of the home
warranty company) that it is illegal to install a furnace larger than
125K BTU in a residential home in California. Is this true? If so,
I'm even more bewildered as to who to trust, as Company C is Sears - a
brand I thought was highly reputable.

Then there was Company D, which is a member of the BBB, has no
complaints filed against them, and is also an authorized installer for
Home Depot. This company provided the most thorough examination of our
home and took into account the materials it was made of, the layout,
and all of the windows, in addition to the square footage, in making
their recommedation. They suggested getting two seperate 80% efficient
100K BTU furnaces and using a "twinning kit" to make the units operate
as one, providing a total of 200K BTU to heat the home. In addition to
seem the most knowledgable of the contractors thus far, they also had
worked with our home warranty company in the past (and is only no
longer on the list of approved contractors b/c they didn't send their
latest proof of insurance over, which they are now doing so that we
might be able to have the home warranty company authorize their doing
the repairs)

When we called the home warranty company and told them of Company D's
recommendations, the home warranty rep who answered told us that
twinning is not a proper furnace installation, and could actually cause
our home to blow up! The home warranty company said they wanted to
send another company out of their choice for a 2nd opinion (the
abovementioned Company E).

When Company E showed up, they told us they would recommend putting in
two 80% efficient 90K BTU units -- that were twinned! We told them
what the home warranty company said about twinning, and they said that
was inaccurate and that they did twinning systems all the time and it
was the only way to heat a home of our size, and that the same home
warranty company had previously authorized such repairs in the past.

Yet when we next spoke with the home warranty company, we found out
that Company E had actually sent in a completely different job estimate
to them, with recommendations of a zoned system with a single 125K 80%
efficient BTU unit for the upstairs, and a 75K 80% eff. unit for the
downstairs. As such, there would be extensive ductwork modification
that would need to be done to zone the system, leaving us with almost
$2900 in uncovered costs.

(thanks for your patience if you're still reading this far!)

By this point I felt like my head was spinning, and could not
understand why the contractor who came to our home would tell us they
would be installing 2 twinned 90K BTU units, only to then send an
estimate to the home warranty company for an entirely different job.
The home warranty rep suggested I call Copmany E and ask why there was
a discrepancy between what they'd told us and what they told the home
warranty company, and to explain why they'd want to do a zoned system
over a twinned system.

I'm already beyond 'house poor', so if I'm going to be spending this
much money I want to know that the job will be done right, that the
house won't "blow up", and that we will actually have enough heat for
our home (particularly the upstairs level)

So I called Company E, and was told that the estimater said he thought
it would be more efficient to do the zoned system. When I expressed my
concern as to whether the single 125k BTU unit could really heat the
2600 sq foot open floor plan windows everywhere upstairs of the house,
which had 11 registers, not to mention the fact that the downstairs
level only has a single register and no returns I was told they'd have
to call the guy who did the estimate and then get back to me. They
later called me back and said "Yeah, he said you could do it as
twinned". I then asked why did he submit it as being a zoned system to
the home warranty company, to which I didn't really get an adequate
response. I also could not get an adequate answer over which would
actually be the better choice for my home, but that if I went with the
twinning it would only save me $235 for the install of a second
thermostat (how can that be? wouldn't all the extra ductwork
modification needed for zoning drop the price down if the system were
twinned?)

I am looking to cut costs b/c I'm pretty broke right now, but not at
the expense of safety, comfort level, or decreasing the value of the
house by not getting the right furnace installed. Meanwhile we have no
heat, and I've no idea which (if any) of these contractors I can trust.


This is my first home, and I've been told by numerous friends who have
been homeowners for far longer that it is *very* difficult to find a
good HVAC contractor - and of course, no one had any they could
recommend. I feel like I just don't have enough information to
possibly make a decision as to whether to go with a twinned system, or
a zoned system, which contractor to choose, etc.

I literally am desperate for some advice from those who are more
knowledgable regarding heating issues. TIA for the help, and also for
having gotten this far in my huge rambling anxious post!!!

  #2   Report Post  
Stretch
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

I do very little gas any more as I live in Heat Pump country now. Your
old furnace sounds way too big. The proper size is determined by doing
a "Load Calculation" that takes into account YOUR weather conditions,
window sizes type and directions, door area, wall area, ceiling area,
floor area and insulation levels for all those things. This involves
following ACCA Manual J, usually with a computer program.

The air flow should be measured to determine if your present ducts are
sized properly.

When I lived in Pennsylvania, we had no trouble twinning furnaces on
large houses. Some furnaces had twinning kits available.

The thing about California law saying 125 K is max furnace size sounds
goofy, but, hey, you five in the goofiest state in the USA.

If you send me your email address with spaces around the "at" and "dot"
I will email you an article on high efficiency installations, which
should save you money in the long run.

Kevin O'Neill
"Stretch"
843-385-2220
O'Neill Bagwell Cooling & Heating
Myrtle Beach, SC

  #3   Report Post  
m Ransley
 
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Default Desperate for advice on replacing dead 255K BTU furnace in3200...

So you have 2600 sq ft in Ca where its not that cold and you think you
need 200k btu or so, Im no pro but you need a written load calculation
done on the house to know what you need in Btu. Did anyone do one? So
you might have been oversized and may still be. Im in zone 5 to -20f
1800sqft on a windy lake and was calculated to need 50k btu on a super
insulated house. I actualy only need my 47000btu 1st stage, never the
78000 second stage. One thing you need new windows and probably
insulation, I would ask for a copy of the written load calc all these
pros did [sure] and go with the smallest unit you can. And look into new
glass, and figure that into your unit size if you can afford it. You
are loosing winter and summer without Low E argon glass, with the heat
up you describe you likely have regular glass.

  #4   Report Post  
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house


wrote:
9 months ago, I put my entire life savings into the down payment for a
home (built in 1955) in the Oakland Hills (northern california)

My fiancé and I recently found out that our monstrous 50 year old 255K
BTU furnace (70% efficiency in its day) has cracks in 4 out of 6 of
the heat exchangers and was emitting carbon monoxide (yikes!). They
no longer make residential furnaces of that size, so deciding how to
replace it has been an exercise in frustration and confusion. We have
gotten 5 separate estimates, all providing vastly different opinions as
to what should be done to replace our furnace and adequately and most
efficiently heat our home. How is one to know who to trust and
believe? My head is spinning from all of the different advice we've
been given (which I'll detail further down in this post)

To complicate things further, our home was custom built by the previous
owner, and has a very unique open floor plan on the upstairs level,
which constitutes about 2600 sq feet of the home. There are 11
registers and 2 large returns on the upstairs level (although both my
office and our dining room have NO registers and we've been told they
can't be added). The downstairs level accounts for approximately 600
square feet and contains our family room (which has a single register
in it)and a guest bedroom with no registers in it.

The entire length of the house, on both levels, has floor to ceiling
windows facing south that provide a breathtaking panoramic view of the
bay. However, they are older windows, with metal frames, and are very
inefficient -- the house loses a lot of heat when it is cold through
those windows, yet when the sun is out the vast southern exposure beams
through the house, heating it sometimes to the point where I literally
feel like a dog locked in a car on a hot summer day. We are in the
hills, and it can get windy, meaning it can get super cold at night.
Yet when the sun is shining, it actually heats up to the point that by
mid-afternoon I'm opening windows because it's too warm -- even in
November (although once the rainy season starts it will be cold all the
time -- I know this from our first month in the house, last February,
wherein we got a $550 PG&E bill that almost gave me a heart attack...
-- after that I had tried not running the heat, but even with wool
sweaters my fingers were still too cold to type and you can't operate a
touchpad with gloves on..)

We have a home warranty, which should cover the cost of replacing the
furnace, although it turns out that the list of uncovered items is much
larger than what is covered.. The home warranty sent out Company A to
provide an estimate for the furnace replacement. They came back with
the suggestion of replacing our 70% efficient 255K BTU furnace with an
80% 100K BTU furnace to the tune of $6300, $2100 of which we would have
to pay out of pocket. As we were shocked both by the price, and by the
size of the unit they were suggesting (how could this adequately heat
our home?), I did a little researching on the Better Business Bureau
website and found Company A had several unresolved complaints filed
against them. Not good.

I decided to get some estimates of my own, and had 3 separate
companies come out to the house. Companies B & C each suggested
getting a single 80% efficiency 155K BTU unit. However, we were
concerned whether even this would provide adequate heating AND we were
informed both by the home warranty company and by Company E (who
provided estimate number 5 as a 2nd opinion on behalf of the home
warranty company) that it is illegal to install a furnace larger than
125K BTU in a residential home in California. Is this true? If so,
I'm even more bewildered as to who to trust, as Company C is Sears - a
brand I thought was highly reputable.

Then there was Company D, which is a member of the BBB, has no
complaints filed against them, and is also an authorized installer for
Home Depot. This company provided the most thorough examination of our
home and took into account the materials it was made of, the layout,
and all of the windows, in addition to the square footage, in making
their recommedation. They suggested getting two seperate 80% efficient
100K BTU furnaces and using a "twinning kit" to make the units operate
as one, providing a total of 200K BTU to heat the home. In addition to
seem the most knowledgable of the contractors thus far, they also had
worked with our home warranty company in the past (and is only no
longer on the list of approved contractors b/c they didn't send their
latest proof of insurance over, which they are now doing so that we
might be able to have the home warranty company authorize their doing
the repairs)

When we called the home warranty company and told them of Company D's
recommendations, the home warranty rep who answered told us that
twinning is not a proper furnace installation, and could actually cause
our home to blow up! The home warranty company said they wanted to
send another company out of their choice for a 2nd opinion (the
abovementioned Company E).

When Company E showed up, they told us they would recommend putting in
two 80% efficient 90K BTU units -- that were twinned! We told them
what the home warranty company said about twinning, and they said that
was inaccurate and that they did twinning systems all the time and it
was the only way to heat a home of our size, and that the same home
warranty company had previously authorized such repairs in the past.

Yet when we next spoke with the home warranty company, we found out
that Company E had actually sent in a completely different job estimate
to them, with recommendations of a zoned system with a single 125K 80%
efficient BTU unit for the upstairs, and a 75K 80% eff. unit for the
downstairs. As such, there would be extensive ductwork modification
that would need to be done to zone the system, leaving us with almost
$2900 in uncovered costs.

(thanks for your patience if you're still reading this far!)

By this point I felt like my head was spinning, and could not
understand why the contractor who came to our home would tell us they
would be installing 2 twinned 90K BTU units, only to then send an
estimate to the home warranty company for an entirely different job.
The home warranty rep suggested I call Copmany E and ask why there was
a discrepancy between what they'd told us and what they told the home
warranty company, and to explain why they'd want to do a zoned system
over a twinned system.

I'm already beyond 'house poor', so if I'm going to be spending this
much money I want to know that the job will be done right, that the
house won't "blow up", and that we will actually have enough heat for
our home (particularly the upstairs level)

So I called Company E, and was told that the estimater said he thought
it would be more efficient to do the zoned system. When I expressed my
concern as to whether the single 125k BTU unit could really heat the
2600 sq foot open floor plan windows everywhere upstairs of the house,
which had 11 registers, not to mention the fact that the downstairs
level only has a single register and no returns I was told they'd have
to call the guy who did the estimate and then get back to me. They
later called me back and said "Yeah, he said you could do it as
twinned". I then asked why did he submit it as being a zoned system to
the home warranty company, to which I didn't really get an adequate
response. I also could not get an adequate answer over which would
actually be the better choice for my home, but that if I went with the
twinning it would only save me $235 for the install of a second
thermostat (how can that be? wouldn't all the extra ductwork
modification needed for zoning drop the price down if the system were
twinned?)

I am looking to cut costs b/c I'm pretty broke right now, but not at
the expense of safety, comfort level, or decreasing the value of the
house by not getting the right furnace installed. Meanwhile we have no
heat, and I've no idea which (if any) of these contractors I can trust.


This is my first home, and I've been told by numerous friends who have
been homeowners for far longer that it is *very* difficult to find a
good HVAC contractor - and of course, no one had any they could
recommend. I feel like I just don't have enough information to
possibly make a decision as to whether to go with a twinned system, or
a zoned system, which contractor to choose, etc.

I literally am desperate for some advice from those who are more
knowledgable regarding heating issues. TIA for the help, and also for
having gotten this far in my huge rambling anxious post!!!


This is Turtle.

As I read your post here i see you have orginized mass confussion
forming here and also have seen a mass amount of bull**** reported to
you. So here is some info that you can use so far.

Twinning of furnaces is nothing but making two furnaces turn off and on
together as one unit. like 2 -- 100K BTU would become 1 -- 200K BTU
furnace.

Now Being informed that you have to replace a 255 k btu furnce on a
house that you bought less than 1 years ago. Louisiana law says if you
buy a house through a realestate dealer. that Dealer will have to fix
anything that was not disclosed in the closing papers for 1 year. I
know
california is different from Louisiana law but you may look into it.

Dealing with a Home insurance company to deal with on repairs is one of
the hardest thing in the world to get done. I see you have the bill of
$6,300.00 and your going to have to pay $2,100.00 of it. this is 1/3 of
the bill and it sounds like the insurance company is sending you to
school. You must be getting this policy dirty cheap for that percent of
the lost that you will have to pay.

these words of not twinning furnaces on residentiual furnaces sounds
like bull**** to me. i have twinned furnace on residentiual application
for a many a year and have no words said about not doing it.

i see your getting a bunch of bull by tring to please a contract and a
insurance company all at one time. You have to get with A hvac
contractor and decide on what is to be done and then call the insurance
company and talk to them.

Now Picking a HVAC contractor. Have him show you his contractor
licences and proof of contractor liability for the area, Ask for
referrences and phone numbers and names to call, He will have to run a
heat load on the house & discuss it with you or don't send me a bid,
and last of all have him talk to you and not your insurance company for
deciding the quality of the job. The insurance company is tring to cut
the cost and the quality of the job down and your tring to get the
quality up on it.

Now don't deal with any contracxtor that does not answser all your
question in a timely manner.

If you like E-Mail me and discuss it.

TURTLE

  #5   Report Post  
Tim Fischer
 
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Default Desperate for advice on replacing dead 255K BTU furnace in3200...


"m Ransley" wrote in message
...
So you have 2600 sq ft in Ca where its not that cold and you think you
need 200k btu or so,


2600 was the "upper level". He also mentioned 600sqft on the "lower level".
Not sure if that makes the house 3200sqft, or if there's other areas not
mentioned...

Still, 3200sqft at 200+kbtu in Cali seems like WAY overkill. We have
2700sqft in Minnesota and our current unit (circa 1980) has a whopping
63kbu. And I'm guessing you don't see many 20-degree-below-zero days in
Cali -- we usually see some every year.

-Tim




  #6   Report Post  
buffalobill
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

you need some sleep.

got a gas kitchen stove? crack open a window a few inches and turn it
on to bake 500, leaving the oven door closed to protect the safety
pilot.

got an ELECTRIC clothes dryer? disconnect its exhaust flex and point it
into the house, set for timed dry, maximum minutes, maximum
temperature. push start

now the pipes can't freeze if you keep them warm at the fixture rooms
such as the bathroom, so plug in some digital thermostat portable
electric heaters, they will throw off 1500 watts of heat.

here's the seasonal averages. pretty nice.
http://www.wunderground.com/NORMS/Di...=none&IATA=SFO

an 80,000btu forced air furnace costs under $600.
plus parts and ducts and pipe and labor.

got wind? put up a windmill.

you need an attorney or insurance adjuster to deal with the insurance
company. once you get that money in your hand you can make your own
deal for the systems you want.

you need to refinance your expensive home with a home equity loan and
have some home repair lines of credit available to you.

every system failure has a silver lining, you're being firmly pushed
into the future savings of energy star.

now that the house is warmed up, read all this:
http://www.energystar.gov/
and this
http://www.energy.ca.gov/title24/changeout/index.html








you need to put your utility company on balanced billing so there are
no surprises in winter.

  #7   Report Post  
Richard J Kinch
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

Quite the essay you have written. That you have a home (non-)warranty, and
faith in the BBB as a quality detector, shows that you have much to learn.
Those two things are prime indicators for "sucker". But my hunch is, you
got suckered on the house itself.

Offhand it sounds like you need to renovate with a zoned hot water system.

A different house might be simpler and cheaper, if the process was informed
by some critical thinking.
  #8   Report Post  
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

wrote

... a home (built in 1955) in the Oakland Hills (northern california)


My Canyon (2 miles from Oakland) CA friends don't believe in insulation,
nor anything else in the building codes :-)

My fianc=E9 and I recently found out that our monstrous 50 year old 255K
BTU furnace (70% efficiency in its day) has cracks...


.... 255K Btu PER HOUR seems like a lot. NREL says 1050 Btu/ft^2 of sun
falls on a south wall on an average 48.7 F January day in San Francisco
with a 55.6 daily max. ASHRAE's 99% winter design temp is 35 F, ie it's
warmer 99% of the time. Solar house heating is _extremely easy_ in SF.

... How is one to know who to trust and believe?


Trust and believe me. Stretch and Turtle are OK, but orthodox. SQlit
is dogmatic, mransley sometimes acts like an arrogant idiot, Meehan
and Radwinski could learn more about heatflow, and so on.

... our home was custom built by the previous owner, and has a very unique
open floor plan on the upstairs level, which constitutes about 2600 sq feet
... The downstairs level accounts for approximately 600 square feet


.... 255K Btu/h for 3200 ft^2? Does this house have walls? :-)
You probably need a blower door test and more insulation.

The entire length of the house, on both levels, has floor to ceiling
windows facing south that provide a breathtaking panoramic view of the bay.


Lovely :-)

... they are older windows, with metal frames, and are very inefficient --


That's OK in CA. A square foot of R1 south window with 90% solar transmission
would gain 0.9x1050 = 945 Btu on an average January day. On a 24-hour living
space, it might lose 24h(65-48.7)1ft^2/R1 = 391 with a net gain of 554. On
a low-thermal mass sunspace, it might lose 6h(70-52) = 108, netting 837.

the house loses a lot of heat when it is cold through those windows, yet
when the sun is out the vast southern exposure beams through the house,
heating it sometimes to the point where I literally feel like a dog locked
in a car on a hot summer day.


Congratulations! You have a solar-heated house! It needs more thermal mass,
maybe upstairs or below the ceiling, with an insulated wall between all
those windows and the 24-hour living space and airflow between the new
"sunspace" and the living space that stops at night.

... it can get windy, meaning it can get super cold at night. Yet when
the sun is shining, it actually heats up to the point that by mid-afternoon
I'm opening windows because it's too warm -- even in November (although
once the rainy season starts it will be cold all the time -- I know this
from our first month in the house, last February...


You might "open windows" with a thermostat and an exhaust fan...

NREL says 830 Btu/ft^2 of sun falls on a south wall on an average 52.2 F
February day in San Francisco with a 60.8 daily max. A square foot of R1
south window would gain 0.9x830 = 747 Btu and lose 24h(65-52.2)1ft^2/R1
= 307, for a net gain of 440. On a low-thermal mass sunspace, it might
lose 6h(70-56.5) = 81, for a net evil gain of 666 on an average Feb day.

I am looking to cut costs b/c I'm pretty broke right now, but not at
the expense of safety, comfort level, or decreasing the value of the
house by not getting the right furnace installed. Meanwhile we have no
heat, and I've no idea which (if any) of these contractors I can trust.


My advice: forswear thy fossil fuels and improve the solar performance.
It's easy, with high-school physics and simple arithmetic.

Nick

  #9   Report Post  
m Ransley
 
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Default Desperate for advice on replacing dead 255K BTU furnace in3200...

A few things others noted, the BBB is a joke for you to put any faith
into. Your prices quoted are sounding very high for what you are being
offered. I don`t know your total heating bill for a year but you say 550
for a month of feb. Figure how much your actual yearly heating bill was.
There are high efficiency condensing furnaces which are the norm here
and do save alot more than an 80% unit. Different manufacturers have
different efficiency ratings , they go from apx 93% to a new unit that
has 97%. The savings difference is figured on the differential of the 2
units. A 97% will save you 21% over an 80%, not 17% as many think . I
personaly would not consider an 80% unit unless yearly heating was only
a few hundred. You say Feb was 550 so im guessing 400 was heat so you
qualify for high efficiency condensing unit, and that was at last years
Ng prices, not todays or in 5 years, my prices are up 70% this year.

You state no ducts can be run to 2 rooms, I find that real hard to
believe that something can`t be done as I have just upgraded a 110 yr
home without heat in 3 rooms. Flex duct for "Spacepack AC" is run
everyday to retrofit old homes and can be enginered to do heat, Ive done
it for a hard to plumb room. With a house of that size you are
forgetting VS DC zoneable systems that will save 25-50% in running the
blower. They are available on the best condensing units and can remove
50% more humidity in summer and give more even winter heat through
slower fan operation.

For 2900 Im getting a Carrier infinity 94% with VSDC and special
thermostat instaled, your price of 6300 for 80% units sounds extremely
excessive.

You had a few unqualified bids that did no load calculation as I see it
ranging from 100k Btu to 200k Btu. 100k btu 80% efficient gives out 80k
Btu heat. 200k outputs 160k Btu. At 96% efficiency 100k outputs 96k Btu
and 200k outputs 192k btu. A 20% increase meaning a 20% smaller unit is
needed. A great difference in output you should consider in sizing is
output and their efficiency.

For probably under 4000$ you could get a 97% VSDC out putting 120000
btu that is equivilant to a 80% 144000 input unit and save winter and
summer through its VS DC motor. With some insulation even this unit
would be oversized for your area.

You need to learn about what you need and what is offered and run some
real numbers on utility, equipment, costs and paybacks. Run the numbers
with todays higher Ng costs and double it for 10 years, then you will
realy see that an 80%er is dumb.

You only need the unit sized to keep you warm on the coldest days
running 24hrs a day, If you are going to keep the place future
insulating will make the difference. Caulking everything will reduce
wind iniltration. Insulating curtains and Cellular shades can take the R
1 windows you have to R 5- 6+ likely that would reduce your Btu needed
by a very great amount. If you can do it figure the load calc several
ways for true sizing needed. I sized and had my AC instaled before I
knew this or insulated, so I regret im oversized and humid. There are
many sites on heating, windows, insulation you need to learn as your
"heating pros" are not helping you they are just instalers. Im no pro
but in zone 5 1800 sq I paid 465 last year for Ng down from 2000 by
doing my own research and following my ideas, not any salesmans.

  #10   Report Post  
m Ransley
 
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Default Desperate for advice on replacing dead 255K BTU furnace in3200...

Yea you trust nick and his math, I trust facts and hands on experiance
of pros.



  #11   Report Post  
Bill
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

I certainly understand your situation... It took everything I had to buy my
house. So been there, done that!

It sounds to me like heating your house is going keep you "broke" from now
until eternity!

So I would look at this long term - what is best in the long range of
things?

I think energy rates are going to keep going up, up, up. So I think the
thing to do would be to eventually install double pane "Energy Star" argon
filled windows in your house. This will *drastically* reduce your heating
and air conditioning costs. And also you should eventually insulate the heck
out of your house.

But this will cost a lot of money, and if you are constantly paying high
heating and air conditioning bills, you may never have the money to make the
improvements...

So what I would do for now is to get the largest heating unit you can get,
and zone the house out. Instead of heating the *entire* house, figure out
which rooms or which portion of the house can be heated while leaving the
rest of the house unheated. (Close doors.) Perhaps you can move your office
elsewhere for the time being?

Then just heat certain rooms or a certain section of the house. This will
save you money on energy bills for the time being. Then maybe you could have
one window replaced a year with an "Energy Star" window - this will be
expensive. Eventually when all windows are replaced and the home is well
insulated, your heating requirements will be much less.

Then you should be able to heat your entire home for a more reasonable cost.
And at that time, you will not need such a large monster furnace!

Here is the Energy Star web site...
http://www.energystar.gov/


  #12   Report Post  
House
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

FYI
I have a 3600SQ feet house + finished basement in Toronto, were it is much
colder than N. California.
Last year I replaced 120,000BTU gas forced air furnace with 100,000BUT High
Efficiency furnace and it is more than enough to keep my house worm.
Is you attic insulated?


wrote in message
oups.com...
9 months ago, I put my entire life savings into the down payment for a
home (built in 1955) in the Oakland Hills (northern california)

My fiancé and I recently found out that our monstrous 50 year old 255K
BTU furnace (70% efficiency in its day) has cracks in 4 out of 6 of
the heat exchangers and was emitting carbon monoxide (yikes!). They
no longer make residential furnaces of that size, so deciding how to
replace it has been an exercise in frustration and confusion. We have
gotten 5 separate estimates, all providing vastly different opinions as
to what should be done to replace our furnace and adequately and most
efficiently heat our home. How is one to know who to trust and
believe? My head is spinning from all of the different advice we've
been given (which I'll detail further down in this post)

To complicate things further, our home was custom built by the previous
owner, and has a very unique open floor plan on the upstairs level,
which constitutes about 2600 sq feet of the home. There are 11
registers and 2 large returns on the upstairs level (although both my
office and our dining room have NO registers and we've been told they
can't be added). The downstairs level accounts for approximately 600
square feet and contains our family room (which has a single register
in it)and a guest bedroom with no registers in it.

The entire length of the house, on both levels, has floor to ceiling
windows facing south that provide a breathtaking panoramic view of the
bay. However, they are older windows, with metal frames, and are very
inefficient -- the house loses a lot of heat when it is cold through
those windows, yet when the sun is out the vast southern exposure beams
through the house, heating it sometimes to the point where I literally
feel like a dog locked in a car on a hot summer day. We are in the
hills, and it can get windy, meaning it can get super cold at night.
Yet when the sun is shining, it actually heats up to the point that by
mid-afternoon I'm opening windows because it's too warm -- even in
November (although once the rainy season starts it will be cold all the
time -- I know this from our first month in the house, last February,
wherein we got a $550 PG&E bill that almost gave me a heart attack...
-- after that I had tried not running the heat, but even with wool
sweaters my fingers were still too cold to type and you can't operate a
touchpad with gloves on..)

We have a home warranty, which should cover the cost of replacing the
furnace, although it turns out that the list of uncovered items is much
larger than what is covered.. The home warranty sent out Company A to
provide an estimate for the furnace replacement. They came back with
the suggestion of replacing our 70% efficient 255K BTU furnace with an
80% 100K BTU furnace to the tune of $6300, $2100 of which we would have
to pay out of pocket. As we were shocked both by the price, and by the
size of the unit they were suggesting (how could this adequately heat
our home?), I did a little researching on the Better Business Bureau
website and found Company A had several unresolved complaints filed
against them. Not good.

I decided to get some estimates of my own, and had 3 separate
companies come out to the house. Companies B & C each suggested
getting a single 80% efficiency 155K BTU unit. However, we were
concerned whether even this would provide adequate heating AND we were
informed both by the home warranty company and by Company E (who
provided estimate number 5 as a 2nd opinion on behalf of the home
warranty company) that it is illegal to install a furnace larger than
125K BTU in a residential home in California. Is this true? If so,
I'm even more bewildered as to who to trust, as Company C is Sears - a
brand I thought was highly reputable.

Then there was Company D, which is a member of the BBB, has no
complaints filed against them, and is also an authorized installer for
Home Depot. This company provided the most thorough examination of our
home and took into account the materials it was made of, the layout,
and all of the windows, in addition to the square footage, in making
their recommedation. They suggested getting two seperate 80% efficient
100K BTU furnaces and using a "twinning kit" to make the units operate
as one, providing a total of 200K BTU to heat the home. In addition to
seem the most knowledgable of the contractors thus far, they also had
worked with our home warranty company in the past (and is only no
longer on the list of approved contractors b/c they didn't send their
latest proof of insurance over, which they are now doing so that we
might be able to have the home warranty company authorize their doing
the repairs)

When we called the home warranty company and told them of Company D's
recommendations, the home warranty rep who answered told us that
twinning is not a proper furnace installation, and could actually cause
our home to blow up! The home warranty company said they wanted to
send another company out of their choice for a 2nd opinion (the
abovementioned Company E).

When Company E showed up, they told us they would recommend putting in
two 80% efficient 90K BTU units -- that were twinned! We told them
what the home warranty company said about twinning, and they said that
was inaccurate and that they did twinning systems all the time and it
was the only way to heat a home of our size, and that the same home
warranty company had previously authorized such repairs in the past.

Yet when we next spoke with the home warranty company, we found out
that Company E had actually sent in a completely different job estimate
to them, with recommendations of a zoned system with a single 125K 80%
efficient BTU unit for the upstairs, and a 75K 80% eff. unit for the
downstairs. As such, there would be extensive ductwork modification
that would need to be done to zone the system, leaving us with almost
$2900 in uncovered costs.

(thanks for your patience if you're still reading this far!)

By this point I felt like my head was spinning, and could not
understand why the contractor who came to our home would tell us they
would be installing 2 twinned 90K BTU units, only to then send an
estimate to the home warranty company for an entirely different job.
The home warranty rep suggested I call Copmany E and ask why there was
a discrepancy between what they'd told us and what they told the home
warranty company, and to explain why they'd want to do a zoned system
over a twinned system.

I'm already beyond 'house poor', so if I'm going to be spending this
much money I want to know that the job will be done right, that the
house won't "blow up", and that we will actually have enough heat for
our home (particularly the upstairs level)

So I called Company E, and was told that the estimater said he thought
it would be more efficient to do the zoned system. When I expressed my
concern as to whether the single 125k BTU unit could really heat the
2600 sq foot open floor plan windows everywhere upstairs of the house,
which had 11 registers, not to mention the fact that the downstairs
level only has a single register and no returns I was told they'd have
to call the guy who did the estimate and then get back to me. They
later called me back and said "Yeah, he said you could do it as
twinned". I then asked why did he submit it as being a zoned system to
the home warranty company, to which I didn't really get an adequate
response. I also could not get an adequate answer over which would
actually be the better choice for my home, but that if I went with the
twinning it would only save me $235 for the install of a second
thermostat (how can that be? wouldn't all the extra ductwork
modification needed for zoning drop the price down if the system were
twinned?)

I am looking to cut costs b/c I'm pretty broke right now, but not at
the expense of safety, comfort level, or decreasing the value of the
house by not getting the right furnace installed. Meanwhile we have no
heat, and I've no idea which (if any) of these contractors I can trust.


This is my first home, and I've been told by numerous friends who have
been homeowners for far longer that it is *very* difficult to find a
good HVAC contractor - and of course, no one had any they could
recommend. I feel like I just don't have enough information to
possibly make a decision as to whether to go with a twinned system, or
a zoned system, which contractor to choose, etc.

I literally am desperate for some advice from those who are more
knowledgable regarding heating issues. TIA for the help, and also for
having gotten this far in my huge rambling anxious post!!!


  #13   Report Post  
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house


wrote:

So I called Company E, and was told that the estimater said he thought
it would be more efficient to do the zoned system.


He's probably right. Your situation sounds like a good fit for zoning.

When I expressed my
concern as to whether the single 125k BTU unit could really heat the
2600 sq foot open floor plan windows everywhere upstairs of the house,
which had 11 registers, not to mention the fact that the downstairs
level only has a single register and no returns


You probably lack qualification to determine whether 11 registers has
anything to do with 125kBTU, but they should be able to give you an
answer if you ask the right questions. They proposed to rework the
ductwork anyway, right? That means they're already seriously thinking
about the air balance and heating needs of the two zones.

I was told they'd have
to call the guy who did the estimate and then get back to me. They
later called me back and said "Yeah, he said you could do it as
twinned".


The answer doesn't match the question. Are you sure your question
didn't mention twinning or whether it could be done cheaper with a
single zone?

I then asked why did he submit it as being a zoned system to
the home warranty company, to which I didn't really get an adequate
response.


The communications between you and the estimator are "filtered" by the
guy on the phone. Chances are good that's where your problem is in
getting adequate response. He might be asking the estimator the
question he thinks you're trying to ask, and giving you the answer he
thinks you want to hear. Ask to speak directly with the estimator if
you can.

Here's what I think happened. The estimator told you his initial
impressions upon seeing the system you already had and ballpark
guestimating by the total square footage of your building. After closer
inspection and further consideration of your unique building, he
determined that you'd be better off with zoning and with certain
deficiencies corrected. So they provided their recommendation to the
warranty company for what you should really get done.

I'm going to guess that your questions give the impression that you're
looking to save costs, so they're offering you a cheaper but less
optimum alternative.

I also could not get an adequate answer over which would
actually be the better choice for my home, but that if I went with the
twinning it would only save me $235 for the install of a second
thermostat (how can that be? wouldn't all the extra ductwork
modification needed for zoning drop the price down if the system were
twinned?)


You have only one register and no return on the first floor? Offhand,
it does not sound like your ductwork is appropriate, but I can't see it
from here. It could be that most of the ductwork modification is to
provide some to the first floor, which you may need in either case.

If you have two stories, generally the better choice for comfort and
energy efficiency is zoned. When you bring costs of installation and
upkeep into the picture, comfort and energy are traded for dollars. For
some, a single zone is "comfortable enough" and "efficient enough" not
to justify the added expense of zoning.

I am looking to cut costs b/c I'm pretty broke right now, but not at
the expense of safety, comfort level, or decreasing the value of the
house by not getting the right furnace installed. Meanwhile we have no
heat, and I've no idea which (if any) of these contractors I can trust.


I think contractor E sounds more "with it" except for the communication
problems, which let's face it might be at least partially on your end
of the phone. It's tough to be an educated consumer untill you've
already consumed a bit ;-)

  #14   Report Post  
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house


Bill wrote:

So what I would do for now is to get the largest heating unit you can get,
and zone the house out. Instead of heating the *entire* house, figure out
which rooms or which portion of the house can be heated while leaving the
rest of the house unheated. (Close doors.) Perhaps you can move your office
elsewhere for the time being?


Installing "the largest heating unit you can get" and then closing off
registers to keep some rooms unheated is a good way to decrease the
lifespan and efficiency of the furnace, making your wallet much lighter
in the long run.

The furnace must be sized for the particulars of the zone(s) it feeds.
If it is desired to have part of the house colder than another, they
should be on separate zones by design.

  #15   Report Post  
Iain McClatchie
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

My Canyon (2 miles from Oakland) CA friends don't believe in insulation,
nor anything else in the building codes :-)


For folks who don't know the Bay Area, Canyon, CA is a famous
place. Check it out:

http://maps.google.com/maps?oi=map&q=Canyon,+CA

It's the green spot between Pinehurst Rd and Shephard Canyon
Rd, right in the middle where it looks like there are almost no
roads. If this guy's got a view of the bay, then he's probably on
the south-west side of Manzanita Way.

Decades ago, a bunch of people decided to build there against
the official wishes of Oakland. They build houses and I think
even short roads, completely without city support. I think they're
on-grid now, after decades of wrangling, but maybe not.

Anyway, I just wanted Nick to know that just from riding around
in the area I can say it gets a *lot* colder there at night than it
does in San Francisco. This guy probably has a monster furnace
because that was cheaper than insulation back when the house
was slapped together.

Nick Solar house heating is _extremely easy_ in SF.

Solar house heating *during the day* is easy near SF. It's the
nights that get you. This guy's probably got 800+ ft^2 of glass
and probably sees days of 20+ degree-days heating. That's
400k BTUs a night just through the glass, he might have to
double that for the total (tons of fresh air). The furnace is just
a bit oversize for such a leaky house, but the house is a bad
design in an environment of pricey fuel.

And thermal storage is hard. Note that this guy is sitting
more-or-less on top of the Hayward fault, probably on a sloping
lot with poor footings, and probably has fairly weak construction.
Placing a few dozen tons of thermal mass on the second floor,
nevermind the ceiling, would be irresponsible (although very
much in character for the neighborhood).

If he's seriously lucky, he's got room on the north side of the
house for some thermal storage, maybe even a basement
cut into the hill with a floor that can take some load. If that's
the case, maybe he could get some sort of loop going
between the downstairs storage area on the north side and
the upstairs southern living space.

Nick ... 255K Btu/h for 3200 ft^2? Does this house have walls?
Nick :-) You probably need a blower door test and more
Nick insulation.

Yep. That could make a serious dent in about half the problem.
But that glass is going to be expensive to replace. If he's near
broke, I think it might be reasonable to consider insulation
against the glass at night. Ugly, inconvenient, and cheap.

Nick Congratulations! You have a solar-heated house! It needs
Nick more thermal mass, maybe upstairs or below the ceiling,
Nick with an insulated wall between all those windows and the
Nick 24-hour living space and airflow between the new
Nick "sunspace" and the living space that stops at night.

Your low-mass sunspace is probably a nonstarter, as it would
mean he has to give up a sizeable fraction of the house for all
but ten hours of the day (and most of those hours he's not home
during the weekdays). My guess is he's got the master
bedroom on the south side as well.

Nick You might "open windows" with a thermostat and an
Nick exhaust fan...

Yep.

OP I am looking to cut costs b/c I'm pretty broke right now,
OP but not at the expense of safety, comfort level, or
OP decreasing the value of the house by not getting the
OP right furnace installed. Meanwhile we have no heat,
OP and I've no idea which (if any) of these contractors I
OP can trust.

Nick My advice: forswear thy fossil fuels and improve the
Nick solar performance. It's easy, with high-school physics
Nick and simple arithmetic.

Thermal storage will cost a lot more than a bigger furnace
and burning more fuel, especially in the short term.

My advice:
1) More insulation, especially attic insulation.
2) Blower test, and then patch those leaks. This could lead
to getting a new door or something, but hopefully it's just
weathersealing. PG&E might pay for the blower test.
3) Thermostat-controlled exhaust fan, for those hot days.
4) Insulation on the windows at night. This is ugly, but maybe
you could do something creative like have interior shutters
that hinge down from the ceiling with a drawstring. The
insulation could be 2 inch thick extruded polystyrene slabs
covered in cloth to make them look nice, and also to help
get a reasonably airtight fit between the insulation and the
window frame when deployed. This could save 2-3 therms
($3-5) per night, if you're disciplined about getting those
shutters down every night before you go to bed.
5) Sweaters.

A big furnace is going to be cheaper than thermal storage.
My wild guess is that you're now burning 1500 therms/year
for heating. You can probably get that down to 600-700
therms/year without thermal storage, assuming the window
insulation. So that says you can probably get away with a
half-size furnace, maybe 100k BTU/hr. The money you
save versus a replacement 225k BTU/hr furnace might
offset most of the cost of the insulation updates.



  #16   Report Post  
HeatMan
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

Gonna kick in a little note here...
"Stretch" wrote in message
oups.com...
I do very little gas any more as I live in Heat Pump country now. Your
old furnace sounds way too big. The proper size is determined by doing
a "Load Calculation" that takes into account YOUR weather conditions,
window sizes type and directions, door area, wall area, ceiling area,
floor area and insulation levels for all those things. This involves
following ACCA Manual J, usually with a computer program.

The air flow should be measured to determine if your present ducts are
sized properly.

When I lived in Pennsylvania, we had no trouble twinning furnaces on
large houses. Some furnaces had twinning kits available.

Some furnaces don't need a twinning kit, just a single communication wire..


The thing about California law saying 125 K is max furnace size sounds
goofy, but, hey, you five in the goofiest state in the USA.

If you send me your email address with spaces around the "at" and "dot"
I will email you an article on high efficiency installations, which
should save you money in the long run.

Kevin O'Neill
"Stretch"
843-385-2220
O'Neill Bagwell Cooling & Heating
Myrtle Beach, SC



  #17   Report Post  
Iain McClatchie
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

Nick You might "open windows" with a thermostat and an exhaust fan...

If I'm right about that 800 ft^2 of glass, and if 400 ft^2 of it is
passing
sunlight, then he's getting 332k BTU on those February days you
quoted. While the sun is up, he'll lose 50k BTU through the windows.
Assuming he loses a good chunk elsewhere and has no significant
thermal storage he'll need to vent over 1000 cfm at 80F (from outside
55F). Not exactly an 8" NuTone bathroom fan.

Nick My advice: forswear thy fossil fuels and improve the solar
Nick performance. It's easy, with high-school physics and simple
Nick arithmetic.

....and many, many tons of water.

  #18   Report Post  
 
Posts: n/a
Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

Iain McClatchie wrote:

Nick You might "open windows" with a thermostat and an exhaust fan...

If I'm right about that 800 ft^2 of glass, and if 400 ft^2 of it is
passing sunlight, then he's getting 332k BTU on those February days...


.... 400 ft^2 of single glass might pass 0.9x250x400 = 90K Btu/h in full sun.

While the sun is up, he'll lose 50k BTU through the windows.


.... and lose (70-56.5)400/R1 = 5.4K Btu/h.

Assuming he loses a good chunk elsewhere and has no significant
thermal storage...


.... Significant improvements are possible.

he'll need to vent over 1000 cfm at 80F (from outside 55F).


.... cfm = (90K-5.4K)/(80-55) = 3384, approximately. With your command
of numbers, you might consider a different preoccupation, eg surgery :-)

Not exactly an 8" NuTone bathroom fan.


Maybe 3 $12 20" window box fans, if he wanted to waste all that solar heat.
Or 2 $55 2470 cfm Lasko fans, or a single whole house fan.

Nick My advice: forswear thy fossil fuels and improve the solar
Nick performance. It's easy, with high-school physics and simple
Nick arithmetic.

...and many, many tons of water.


With enough insulation, it wouldn't need any water, nor windows.

A 32' R32 cube with no air infiltration would need 24h(65-48.7)5x32^2/32
= 62.6K Btu on an average Jan day in SF. It might come from 18.3 kWh/day
or 550 kWh/mo of internal electrical usage, 2/3 of the 833 US average.

With no internal heat gain, it might stay warm for 5 cloudy days with
5x62.6K/(130-80)/2000 = 3.13 tons of water cooling from 130 to 80 F in
a 3.13x2000/1024/62.33x12 = 1.2" layer under the 4th floor ceiling. If
A ft^2 of R1 sunspace glazing with 90% solar transmission over the R32
south wall gains 945A Btu/day and loses 6h(130-56.5)A = 441A and makes
62.6K Btu net, A = 124 ft^2, eg an 8'x16' sunspace or $200 patch of
polycarbonate solar siding.

Solar house heating is extremely easy in San Francisco.

Nick

  #19   Report Post  
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

A 32' R32 cube with no air infiltration would need 24h(65-48.7)5x32^2/32
= 62.6K Btu on an average Jan day in SF... With no internal heat gain,
it might stay warm for 5 cloudy days with 5x62.6K/(130-80)/2000 = 3.13
tons of water cooling from 130 to 80 F in a 3.13x2000/1024/62.33x12
= 1.2" layer under the 4th floor ceiling.


The 1st floor ceiling would be better, with less insulation above it and
less heat loss to the outdoors.

If A ft^2 of R1 sunspace glazing with 90% solar transmission over the R32
south wall gains 945A Btu/day and loses 6h(130-56.5)A = 441A and makes
62.6K Btu net, A = 124 ft^2, eg an 8'x16' sunspace or $200 patch of
polycarbonate solar siding.


ie 945A - 441A = 62.6K makes A = 124 ft^2.

Solar house heating is extremely easy in San Francisco.


Nick

  #20   Report Post  
Solar Flare
 
Posts: n/a
Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

Solar mass is just plain cheating though...LOL

wrote in message
...
A 32' R32 cube with no air infiltration would need 24h(65-48.7)5x32^2/32
= 62.6K Btu on an average Jan day in SF... With no internal heat gain,
it might stay warm for 5 cloudy days with 5x62.6K/(130-80)/2000 = 3.13
tons of water cooling from 130 to 80 F in a 3.13x2000/1024/62.33x12
= 1.2" layer under the 4th floor ceiling.


The 1st floor ceiling would be better, with less insulation above it and
less heat loss to the outdoors.

If A ft^2 of R1 sunspace glazing with 90% solar transmission over the R32
south wall gains 945A Btu/day and loses 6h(130-56.5)A = 441A and makes
62.6K Btu net, A = 124 ft^2, eg an 8'x16' sunspace or $200 patch of
polycarbonate solar siding.


ie 945A - 441A = 62.6K makes A = 124 ft^2.

Solar house heating is extremely easy in San Francisco.


Nick





  #21   Report Post  
Iain McClatchie
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

Iain 332k BTU on those February days...
Nick 90K Btu/h in full sun.

Iain lose 50k BTU through the windows.
Nick 5.4K Btu/h.

We're in agreement here, Nick.

Iainhe'll need to vent over 1000 cfm at 80F (from outside 55F).

I calculated 1500 cfm for venting the incoming radiation as heat at 80F
from 55F, averaged across the few hours of insolation. But I figured
he'd lose some through the rest of the house. Your number, below,
is at the peak heating rate and assumes no other loss. Both of us,
incorrectly, assume that the full area of the window is insolated.

Nick cfm = (90K-5.4K)/(80-55) = 3384, approximately.

"Cancelling" air's 0.02 BTU/ft^3-F and 60 minutes/hour, so nobody can
follow your units.

Iain...and many, many tons of water.

Nick With enough insulation, it wouldn't need any water, nor windows.

And *right here* is where you miss your opportunity to help a lot of
people.

The windows make this house. The interior was deliberately opened
up so that most rooms could see the incredible views. If the house
had no windows, your penpal would have bought a different house.

As you keep pointing out with your cube analysis, we could live
comfortably on far less energy. In fact, people all over the earth
do just that every day.

But you advocate going farther down the path of form following function
than most people care to. Ultimately, that gets you ignored by most
folks, and defeats any aspirations you might have to lowering overall
consumption. Windows are not put in houses primarily to gather heat.
They are there to make us happy.

Engineering analysis that says not to put in the windows is not useful.
To be useful, analysis must minimize energy consumption while
constrained to other, more important goals, like having a nice view or
cheery lighting most mornings, or having the house look a certain way.

A house in a 4000 degree-day environment can get through cold sunny
days just fine with solar heating alone so long as it can store the
heat.
If the heat will be stored in the habitable envelope, the water will
only
swing about 10 F before things get uncomfortable. We can fairly easily
guess the volume and surface area of this storage, and with R1
windows it is essentially a foot-thick sheet of water the size of the
windows. Modern glassy houses thus need to contain very large
amounts of water, or even larger amounts of something else to store
their heat. This isn't usually practical in a retrofit.

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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

Iain McClatchie wrote:

Nick With enough insulation, it wouldn't need any water, nor windows.


Windows are bad. They are expensive, and installing them is expensive,
and the framing leaks heat, and they can leak heat and air and water and
sometimes bugs and burglars. Let's replace windows with outdoor cameras
and computer projectors or flat screen TVs, with fluorescent lights and
doors or push-out panels for fire escapes.

The windows make this house. The interior was deliberately opened
up so that most rooms could see the incredible views.


For drama, you might put windows or a single layer of polycarbonate glazing
on an isolated low-mass sunspace with an enclosed solar staircase roof and
a dark mesh curtain near the windows.

A house in a 4000 degree-day environment can get through cold sunny
days just fine with solar heating alone so long as it can store the heat.
If the heat will be stored in the habitable envelope, the water will
only swing about 10 F before things get uncomfortable.


A thin layer of 120 F water goes in a lay-flat poly film duct above
a low-e ceiling surface in the living space heated by hot air from
a sunspace during the day. At night, the sunspace gets cold and
the airflow stops and a slow ceiling fan with a room temp thermostat
and an occupancy sensor warms room air as needed.

Nick

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Edwin Pawlowski
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

wrote in message

Nick With enough insulation, it wouldn't need any water, nor windows.


Windows are bad. They are expensive, and installing them is expensive,
and the framing leaks heat, and they can leak heat and air and water and
sometimes bugs and burglars. Let's replace windows with outdoor cameras
and computer projectors or flat screen TVs, with fluorescent lights and
doors or push-out panels for fire escapes.


Perhaps this is so, but at some point you have to say "screw efficiency" and
look out a real window at real life and allow sunshine into the room.


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Solar Flare
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

Other wise S.A.D.S. sets in and then you become a Usenet addict

"Edwin Pawlowski" wrote in message
. ..
wrote in message

Nick With enough insulation, it wouldn't need any water, nor windows.


Windows are bad. They are expensive, and installing them is expensive,
and the framing leaks heat, and they can leak heat and air and water and
sometimes bugs and burglars. Let's replace windows with outdoor cameras
and computer projectors or flat screen TVs, with fluorescent lights and
doors or push-out panels for fire escapes.


Perhaps this is so, but at some point you have to say "screw efficiency" and
look out a real window at real life and allow sunshine into the room.




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Iain McClatchie
 
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Default Desperate for advice on replacing dead 255K BTU furnace in 3200 sq foot house

Nick Let's replace windows with outdoor cameras and computer
Nick projectors or flat screen TVs, with fluorescent lights and
Nick doors or push-out panels for fire escapes.

So you see how untenable this position is.

I was thinking a little more about the OP's issues heating his house.
It sounds like he's on a south-facing slope. Some of the slopes in
that area are steep enough that his lower floor may be off the ground
on piers which are illuminated by the sun. Alternatively, there is
2000 ft^2 of upper floor not over lower floor, which may also be on
sunlit piers.

In either case, he might be able to build one of your solar closets
down among his sunlit piers, then use air blown through that to heat
the house at night. It would make the house much more usable, increase
resale value, and aesthetic issues with DIY-built stuff would be less
important since it's out of (his) sight. Also, in that neighborhood a
homebuilt solar closet may not generate adverse comments from the
neighbors.

If he can pick up 600 BTU/ft^2/day in February, store it through much
of the night, fix the worst of his air leaks, and add some attic
insulation, he might get half his heating done with 400 ft^2 of solar
aperture and 500 gallons swinging between 90 F and 140 F. That'll save
a bundle on the replacement furnace and the bills from same. Depending
on the house configuration, there may be 40 lateral feet of sunlit
piers down there, so there is some chance of fitting significant solar
aperture. On steep hillsides, angling the solar closet glazing
slightly (15 degrees) face-up from simply vertical can greatly increase
the vertical extent of the glazing without chewing up a lot of real
estate. He might implement a 10 or even 20 foot tall face for the
collector.

If I were going to do any such thing:
- I'd get a contractor to build the footing and concrete pad
under the house for the heat store. Someone used to
doing foundation work, who won't screw up the existing
footings. Have them drill a pier to bedrock if necessary.
- I'd go big on the heat store. 1000 gallons if you can manage it.
- Use 55-gallon (or 40-gallon if you can get them) used plastic
barrels to store the water.
- Build the glazing as tall as possibly practical. It doesn't weigh
very much and often people don't use steep real estate below
their house.
- Heat the water directly rather than use an air heater to transfer
heat to the water. The EPDM mats seem like a nice solution,
but you'll not like the $5/ft^2 price.

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