Hi,
My home is 12 years old and I am looking to save on home heating costs.

I read somewhere that an old furnace loses its efficiency and if its 10
years old, it is only 55% efficient. Is this true? My furnace is a gas
furnace and is 12 years old.

1) If so, I am thinking of replacing it with a new one. What's the best
one out there that is 95% efficient?
How much should I expect to pay for it and also for installation?

I live in Chicago.

2) Also, is it a good idea to replace my water heaters (also gas)? Is
it better to replace them (I have 2) with "tankless water heaters". Are
tankless water heaters installed in the bathrooms or can they go in the
basement?

3) I am thinking of adding a few more inches of insulation in the attic
but concerned that too much of it may lead to condensation which could
result in mold. Any ideas on this?

Thanks.

wrote in message
ups.com...
Hi,
My home is 12 years old and I am looking to save on home heating costs.

I read somewhere that an old furnace loses its efficiency and if its 10
years old, it is only 55% efficient. Is this true? My furnace is a gas
furnace and is 12 years old.

1) If so, I am thinking of replacing it with a new one. What's the best
one out there that is 95% efficient?
How much should I expect to pay for it and also for installation?

I live in Chicago.

2) Also, is it a good idea to replace my water heaters (also gas)? Is
it better to replace them (I have 2) with "tankless water heaters". Are
tankless water heaters installed in the bathrooms or can they go in the
basement?

3) I am thinking of adding a few more inches of insulation in the attic
but concerned that too much of it may lead to condensation which could
result in mold. Any ideas on this?

Thanks.

There is no one that can answer your questions blind.

You have to decide the costs for yourself. The location and installation
for every situation is different. Sometimes not much but enough that the
safety of your home could be at stake.

http://www.hvacopcost.com/

http://198.147.238.24/ac_calc/default.asp

What you install is directly related to how long you plan to stay and the
ROI.

Insulation/weather stripping is always a good bet especially in older home.
I added R-30 cellulose to my 1977 home this year in July. A/C bill was less
than 1/2 in August. Not a true measure but worth the $300 bucks I paid the
contractor to do the job. All of the electric bills have been down more
than 40% since.

My investigation into tankless heaters proved to me that they were not for
me. Check the rate of rise, then guess at what your winter incoming water
temps are. That was the deal breaker for me.

Thanks for your reply. The links you posted are quite useful.

My one question is:

Is it true that a forced air gas furnace loses its efficiency down to
55%, once its 10 years old?

Thanks.

wrote:
Thanks for your reply. The links you posted are quite useful.

My one question is:

Is it true that a forced air gas furnace loses its efficiency down to
55%, once its 10 years old?

Thanks.

Not according to my plumber ad the Energy Survey I had done. 35 years
old and still 83%.

wrote in message
oups.com...
: Thanks for your reply. The links you posted are quite useful.
:
: My one question is:
:
: Is it true that a forced air gas furnace loses its efficiency
down to
: 55%, once its 10 years old?
:
: Thanks.
:
No, they do not. The design and components making up a furnace
are such that it either works or it doesn't. Plugged orfices,
leaking ductwork, fan motors, etc etc all wear out but not the
heat producing physics of the materials. If it makes the right
flame, it's still very close to what it originally was.

HTH,

Pop

"Christian Fox" wrote in message
...
: In article
. com,

: says...
: I read somewhere that an old furnace loses its efficiency and
if its 10
: years old, it is only 55% efficient. Is this true? My furnace
is a gas
: furnace and is 12 years old.
: 1) If so, I am thinking of replacing it with a new one. What's
the best
: one out there that is 95% efficient?
: How much should I expect to pay for it and also for
installation?
:
: Unless the furnace has reached the end of its lifespan, it's
probably going to cost you a
: lot more to replace it than you'll ever save by putting in a
higher-efficiency model.
: It'd probably make more sense to wait until the furnace is
closer to the end of its life
: (it should last at least 15 years, and possibly much longer)
before you replace it.
:
: As to the costs, the only way to find out is to get some HVAC
contractors out and get
: estimates. There are too many variables involved to give you
an accurate answer.
:
: 2) Also, is it a good idea to replace my water heaters (also
gas)? Is
: it better to replace them (I have 2) with "tankless water
heaters". Are
: tankless water heaters installed in the bathrooms or can they
go in the
: basement?
:
: Tankless water heaters usually get installed in the basement
and service the whole house.
: If you have enough demand for hot water to require two regular
hot water tanks, you're
: not likely to be happy with a tankless model. Tankless water
heaters have limits to the
: amount of hot water they can produce at any given time.
:
: 3) I am thinking of adding a few more inches of insulation in
the attic
: but concerned that too much of it may lead to condensation
which could
: result in mold. Any ideas on this?
:
: You can add tons of insulation to the attic, and it shouldn't
cause any condensation at
: all as long as the insulation doesn't block the ventilation.
The attic should be vented
: at the soffits and at the peaks, creating a draft that flows
through from bottom to top.
:
: Whether the insulation will reduce your heating costs, however,
is a different story - if
: your house is only 12 years old, it probably has adequate
insulation already.
:

Many people miss the idea that insulation thickness has a point
of diminishing returns. The first few inches makes an incredible
difference. Succeeding inches add successively less heat loss
protection per each inch. Once the optimum thickness point is
reached, more insulation becomes a negligible help; other factors
become more important.
It's a logarithmic curve if that helps; rises fast, then slope
becomes gradually less and less, approaching zero (flat)
eventually. When it's REALLY cold out and touching a wall feels
resonably warm, you're at or near the point of diminishing
returns. Assuming proper installation, that is.

I know it varies by region, but I wonder what that optimum
thickness is? Anyone know? Neglecting reflective surface, etc
etc etc..
I suspect it's around 8 or 9 inches, but that's just a guess;
anything over about 6" seems to make very little difference.

HTH,

Pop

SQLit wrote:

wrote in message
ups.com...

Hi,
My home is 12 years old and I am looking to save on home heating costs.

I read somewhere that an old furnace loses its efficiency and if its 10
years old, it is only 55% efficient. Is this true? My furnace is a gas
furnace and is 12 years old.

1) If so, I am thinking of replacing it with a new one. What's the best
one out there that is 95% efficient?
How much should I expect to pay for it and also for installation?

I live in Chicago.

2) Also, is it a good idea to replace my water heaters (also gas)? Is
it better to replace them (I have 2) with "tankless water heaters". Are
tankless water heaters installed in the bathrooms or can they go in the
basement?

3) I am thinking of adding a few more inches of insulation in the attic
but concerned that too much of it may lead to condensation which could
result in mold. Any ideas on this?

Thanks.


There is no one that can answer your questions blind.

You have to decide the costs for yourself. The location and installation
for every situation is different. Sometimes not much but enough that the
safety of your home could be at stake.

http://www.hvacopcost.com/

http://198.147.238.24/ac_calc/default.asp

FWIW, unless I'm doing something wrong, that site seems to yield
usage numbers more than double what I actually use.


What you install is directly related to how long you plan to stay and the
ROI.

Insulation/weather stripping is always a good bet especially in older home.
I added R-30 cellulose to my 1977 home this year in July. A/C bill was less
than 1/2 in August. Not a true measure but worth the $300 bucks I paid the
contractor to do the job. All of the electric bills have been down more
than 40% since.

My investigation into tankless heaters proved to me that they were not for
me. Check the rate of rise, then guess at what your winter incoming water
temps are. That was the deal breaker for me.




--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Most 12 yr old furnaces were 80% efficient and will remain 80% if
maintained. I would just turn off one tank and see if that does it ok
for you Chicago water is apx 45f now , turn off the second tank and
leave the first one in line to temper the water to room temp. I pulled
out a 20 yr old tank in Chgo recently it had 12" of sediment, and a
yellow flame it probably was down 40% in efficiency. Tankless are
expensive but save the most. I would look at R 50-60 for your attic
where you are. Be sure you get a written load calculation before you buy
a furnace. Alot of tank loss is up the chimney, if one will do it it
will be cheaper to run, I left in my tank as a tempering tank when I put
in mt tankless, my savings give an apx 4 yr payback.