I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.

I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.

There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?
--
Replace you know what by j to email

Jud McCranie wrote:

I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.

I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.

There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?

Your real estate agent also does air conditioning?

Let the HVAC guys size your unit. That said, savings depend
upon a lot of factors, far too many to review right here. You
can get an idea of the savings based on the chart at this site:

http://www.ehwhitson.com/seer_rating.htm

Just upsize by 25% and that should tell you what you want to know.

--
Robert Allison
Rimshot, Inc.
Georgetown, TX

Jud McCranie wrote:
I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.

I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.

There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?
Hi,
If that pump has been running well, it has few more years life left.
B4 you decide to spend for upgrading, how about air
tightness(insulation) of your house? SEER 10.5 is of course outdated to
today's standard but to get real improvement you have to deal with whole
package, not only one component of a system.(like air handler, etc.)
What is your electric rate? I pay 7 cents/KWh.

On Tue, 18 Sep 2007 19:47:04 -0400, Jud McCranie
wrote:

I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.

I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.

There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?

A real estate agent is in no way, shape, form or fashion qualified to
say if a heat pump is oversized. call a licensed hvac contractor and
have the m do a manual J load calculation. That is the ONLY way you
will know for sure.

Robert Allison wrote:

Jud McCranie wrote:

I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.

I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.

There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?


Your real estate agent also does air conditioning?

Let the HVAC guys size your unit. That said, savings depend upon a lot
of factors, far too many to review right here. You can get an idea of
the savings based on the chart at this site:

http://www.ehwhitson.com/seer_rating.htm

Just upsize by 25% and that should tell you what you want to know.

From that page:

"The following data is based on a 3-ton system (36,000 BTUH) at 9 cents
per KWH at 2800 annual hours of use."

2800 annual hours of use? I hope they don't mean that's how many hours
they assume it runs in a year. Even on a hot day here in Texas, our
unit only runs about 10 hours. And while it's warm here much of the
year, the heavy AC season is only about 4 months long. Maybe if I have
some spare time, I'll add up the minutes our AC ran last year (I have it
instrumented); I'm pretty sure it's nowhere near 2800 hours.

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

"CJT" wrote in message
...
Robert Allison wrote:

Jud McCranie wrote:

I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.

I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.

There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?


Your real estate agent also does air conditioning?

Let the HVAC guys size your unit. That said, savings depend upon a lot
of factors, far too many to review right here. You can get an idea of
the savings based on the chart at this site:

http://www.ehwhitson.com/seer_rating.htm

Just upsize by 25% and that should tell you what you want to know.

From that page:

"The following data is based on a 3-ton system (36,000 BTUH) at 9 cents
per KWH at 2800 annual hours of use."

2800 annual hours of use? I hope they don't mean that's how many hours
they assume it runs in a year. Even on a hot day here in Texas, our
unit only runs about 10 hours. And while it's warm here much of the
year, the heavy AC season is only about 4 months long. Maybe if I have
some spare time, I'll add up the minutes our AC ran last year (I have it
instrumented); I'm pretty sure it's nowhere near 2800 hours.


The best way to figure operational cost is too use the areas Cooling/Heating
degree days and know what size unit you are going to be operating.
Have that and the cost of your utilities, you can get very close to the
actual operational cost.

CJT wrote:

Robert Allison wrote:

Jud McCranie wrote:

I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.

I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.

There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?



Your real estate agent also does air conditioning?

Let the HVAC guys size your unit. That said, savings depend upon a
lot of factors, far too many to review right here. You can get an
idea of the savings based on the chart at this site:

http://www.ehwhitson.com/seer_rating.htm

Just upsize by 25% and that should tell you what you want to know.

From that page:

"The following data is based on a 3-ton system (36,000 BTUH) at 9 cents
per KWH at 2800 annual hours of use."

2800 annual hours of use? I hope they don't mean that's how many hours
they assume it runs in a year. Even on a hot day here in Texas, our
unit only runs about 10 hours. And while it's warm here much of the
year, the heavy AC season is only about 4 months long. Maybe if I have
some spare time, I'll add up the minutes our AC ran last year (I have it
instrumented); I'm pretty sure it's nowhere near 2800 hours.

I realized I could get at the number another way (I know about how many
KWH I use for cooling each year, and about how many watts the AC and
air handler consume while running). In a year, our AC runs about 1600
hours. 2800 seems way high to me.

Austin, Texas

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

CJT wrote:

CJT wrote:

Robert Allison wrote:

Jud McCranie wrote:

I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.

I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.

There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?




Your real estate agent also does air conditioning?

Let the HVAC guys size your unit. That said, savings depend upon a
lot of factors, far too many to review right here. You can get an
idea of the savings based on the chart at this site:

http://www.ehwhitson.com/seer_rating.htm

Just upsize by 25% and that should tell you what you want to know.

From that page:

"The following data is based on a 3-ton system (36,000 BTUH) at 9
cents per KWH at 2800 annual hours of use."

2800 annual hours of use? I hope they don't mean that's how many hours
they assume it runs in a year. Even on a hot day here in Texas, our
unit only runs about 10 hours. And while it's warm here much of the
year, the heavy AC season is only about 4 months long. Maybe if I have
some spare time, I'll add up the minutes our AC ran last year (I have it
instrumented); I'm pretty sure it's nowhere near 2800 hours.

I realized I could get at the number another way (I know about how many
KWH I use for cooling each year, and about how many watts the AC and
air handler consume while running). In a year, our AC runs about 1600
hours. 2800 seems way high to me.

Austin, Texas

FWIW, our peak day this year was August 12. Our AC ran for 11 hours 40
minutes.

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

"CJT" wrote in message
...

FWIW, our peak day this year was August 12. Our AC ran for 11 hours 40
minutes.


Straight or in a 24 hr period?

kjpro @ usenet.com wrote:

"CJT" wrote in message
...


FWIW, our peak day this year was August 12. Our AC ran for 11 hours 40
minutes.



Straight or in a 24 hr period?


In a 24 hour period, midnight to midnight.

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

"CJT" wrote in message
...
kjpro @ usenet.com wrote:

"CJT" wrote in message
...


FWIW, our peak day this year was August 12. Our AC ran for 11 hours 40
minutes.



Straight or in a 24 hr period?


In a 24 hour period, midnight to midnight.


I hope that wasn't at design temperature.

CJT wrote:

Robert Allison wrote:

Jud McCranie wrote:

I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.

I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.

There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?



Your real estate agent also does air conditioning?

Let the HVAC guys size your unit. That said, savings depend upon a
lot of factors, far too many to review right here. You can get an
idea of the savings based on the chart at this site:

http://www.ehwhitson.com/seer_rating.htm

Just upsize by 25% and that should tell you what you want to know.

From that page:

"The following data is based on a 3-ton system (36,000 BTUH) at 9 cents
per KWH at 2800 annual hours of use."

2800 annual hours of use? I hope they don't mean that's how many hours
they assume it runs in a year. Even on a hot day here in Texas, our
unit only runs about 10 hours. And while it's warm here much of the
year, the heavy AC season is only about 4 months long. Maybe if I have
some spare time, I'll add up the minutes our AC ran last year (I have it
instrumented); I'm pretty sure it's nowhere near 2800 hours.


Ours runs pretty much one hour on, one hour off in the summer,
which lasts about 9 months here in central Texas. It gets
down to about 85 at night in the summer, so it is on even
then, just not as much.

So, 270 days of cooling at 12 hours a day equals: 3240

--
Robert Allison
Rimshot, Inc.
Georgetown, TX

"Jud McCranie" wrote in message
...
I'm trying to estimate how long it would take to recoup my
investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent
said
that it was oversized, so me might could use a smaller one.

snip
I'm not an a/c person, but as a home owner, just had recent
experience.
Our 11 year old A/C - heat pump went out and we had it replaced;
the outside unit, the air handler in the attic, and larger return
air vent pipe. (We had 16 inch and the A/C people recommended 18
inch). All in all the whole thing was $7,300. Our next month
electric bill was less by $80.00. There could be other factors
involved in that as well, but no doubt it was cheaper.

It would take a very long time to pay for the new unit with the
savings, so if that is why you are considering it, I doubt it would
be worthwhile.

One more thing, there are two types of Freon units. (I forget the
numbers). The old type is going to be discontinued in a couple
years and the price will sky rocket like the old style auto Freon.
I'd suggest that if you get a new unit that you get the new Freon
type.
Bob-tx

On Wed, 19 Sep 2007 02:13:57 GMT, Tony Hwang wrote:

What is your electric rate? I pay 7 cents/KWh.

It varies according to the season and according to how much you use.
It is higher in the summer. The first 1000 kWh are one rate, then it
goes up. Then it goes up again at 2500 or something like that. I
think the top rate is over 10 cents / kWh and we hit that in the
summer.
--
Replace you know what by j to email

Jud McCranie wrote:
On Wed, 19 Sep 2007 02:13:57 GMT, Tony Hwang wrote:


What is your electric rate? I pay 7 cents/KWh.


It varies according to the season and according to how much you use.
It is higher in the summer. The first 1000 kWh are one rate, then it
goes up. Then it goes up again at 2500 or something like that. I
think the top rate is over 10 cents / kWh and we hit that in the
summer.
Hi,
I see. I live up here in Calgary Alberta. For next 5 years my rate is
locked in at 7 cents per KWh. If ever rate drops(most unlikely) I can
cancel the deal any time with two months notice. Right now going rate
is 11 cents.

Bob wrote:

"Jud McCranie" wrote in message
...

I'm trying to estimate how long it would take to recoup my
investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent
said
that it was oversized, so me might could use a smaller one.


snip
I'm not an a/c person, but as a home owner, just had recent
experience.
Our 11 year old A/C - heat pump went out and we had it replaced;
the outside unit, the air handler in the attic, and larger return
air vent pipe. (We had 16 inch and the A/C people recommended 18
inch). All in all the whole thing was $7,300. Our next month
electric bill was less by $80.00. There could be other factors
involved in that as well, but no doubt it was cheaper.

It would take a very long time to pay for the new unit with the
savings, so if that is why you are considering it, I doubt it would
be worthwhile.

One more thing, there are two types of Freon units. (I forget the
numbers). The old type is going to be discontinued in a couple
years and the price will sky rocket like the old style auto Freon.
I'd suggest that if you get a new unit that you get the new Freon
type.
Bob-tx


Hi,
Like old R22 vs R410a something like that? Carrier calls it Puron.
R22 equipment won't be made after 3 years from now and R22 production
will diminish slowly in next 30 years or so I heard. Our a/c runs on
Puron.

On Sep 19, 11:15 am, Tony Hwang wrote:
Bob wrote:
"Jud McCranie" wrote in message
.. .

I'm trying to estimate how long it would take to recoup my
investment
if I buy a more efficient heat pump.

The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent
said
that it was oversized, so me might could use a smaller one.

snip
I'm not an a/c person, but as a home owner, just had recent
experience.
Our 11 year old A/C - heat pump went out and we had it replaced;
the outside unit, the air handler in the attic, and larger return
air vent pipe. (We had 16 inch and the A/C people recommended 18
inch). All in all the whole thing was $7,300. Our next month
electric bill was less by $80.00. There could be other factors
involved in that as well, but no doubt it was cheaper.

It would take a very long time to pay for the new unit with the
savings, so if that is why you are considering it, I doubt it would
be worthwhile.

One more thing, there are two types of Freon units. (I forget the
numbers). The old type is going to be discontinued in a couple
years and the price will sky rocket like the old style auto Freon.
I'd suggest that if you get a new unit that you get the new Freon
type.
Bob-tx

Hi,
Like old R22 vs R410a something like that? Carrier calls it Puron.
R22 equipment won't be made after 3 years from now and R22 production
will diminish slowly in next 30 years or so I heard. Our a/c runs on
Puron.- Hide quoted text -

- Show quoted text -


If his total yearly estimated electric bill for his heat pump to heat
and cool his house is only around $1000, I think it's very unlikely
he's going to save enough in electricity to justify getting a new
higher efficiency unit.

On Wed, 19 Sep 2007 01:40:52 GMT, Robert Allison
wrote:

Your real estate agent also does air conditioning?

Let the HVAC guys size your unit.

Thanks for the recommendation of the chart.

It is hard for me to trust HVAC people on such matters. Last year my
parents got new units for two houses. One has two stories, six
bedrooms, 5.5 baths, and seven other rooms and they sized it at 2
tons. Now the inside of their house is mildewing because it can't
keep it cool or dry. The other house is one small story, three
bedrooms, two baths, 2 other rooms, and they (different person) sized
it at 4 tons. I told my parents that, if anything, they should have
put the 4 ton unit in the big house and the 2 ton unit in the small
house.

--
Replace you know what by j to email

Jud McCranie wrote:
On Wed, 19 Sep 2007 01:40:52 GMT, Robert Allison
wrote:


Your real estate agent also does air conditioning?

Let the HVAC guys size your unit.


Thanks for the recommendation of the chart.

It is hard for me to trust HVAC people on such matters. Last year my
parents got new units for two houses. One has two stories, six
bedrooms, 5.5 baths, and seven other rooms and they sized it at 2
tons. Now the inside of their house is mildewing because it can't
keep it cool or dry. The other house is one small story, three
bedrooms, two baths, 2 other rooms, and they (different person) sized
it at 4 tons. I told my parents that, if anything, they should have
put the 4 ton unit in the big house and the 2 ton unit in the small
house.

All you need to do is hang around here for a while (or, better still,
alt.hvac) to know that there are plenty of alleged "professionals" in
the business who don't know squat.

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

Jud McCranie wrote:
On Wed, 19 Sep 2007 01:40:52 GMT, Robert Allison
wrote:

Your real estate agent also does air conditioning?

Let the HVAC guys size your unit.

Thanks for the recommendation of the chart.

It is hard for me to trust HVAC people on such matters. Last year my
parents got new units for two houses. One has two stories, six
bedrooms, 5.5 baths, and seven other rooms and they sized it at 2
tons. Now the inside of their house is mildewing because it can't
keep it cool or dry. The other house is one small story, three
bedrooms, two baths, 2 other rooms, and they (different person) sized
it at 4 tons. I told my parents that, if anything, they should have
put the 4 ton unit in the big house and the 2 ton unit in the small
house.

They first should have gotten a heat load on both homes to show them what
proper size was needed.

--
Moe Jones
HVAC Service Technician
Energy Equalizers Inc.
Houston, Texas
www.EnergyEqualizers.com

kjpro @ usenet.com wrote:

"CJT" wrote in message
...

kjpro @ usenet.com wrote:


"CJT" wrote in message
...



FWIW, our peak day this year was August 12. Our AC ran for 11 hours 40
minutes.



Straight or in a 24 hr period?



In a 24 hour period, midnight to midnight.



I hope that wasn't at design temperature.


Whatever design parameters were used 25 years ago when the house was
built have been forgotten long ago. And the original designer couldn't
have known what temperature profile I would now set in my programmable
thermostat (especially since I don't think such thermostats were even
on the market yet back then), nor could (s)he have known that I would
have installed a radiant barrier in my attic, nor many other factors
that affect the AC load. So there's really not much sense in discussing
whether the peak day this year was at "design temperature" or not. In
fact, one might argue that design by rule can't hope to get very close
to the "right" answer, particularly when load patterns can change over
time (e.g. I could install more insulation or the insulation I have
could compact and lose its effectiveness, I could throw more/fewer
parties with lots of heat-exhaling guests, global warming could affect
the climate, I could plant trees which over time could mature and shade
the house, I could install blinds and draperies, I could paint the
house a different color and install a different color roof, etc.).

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

"CJT" wrote in message
...
kjpro @ usenet.com wrote:

"CJT" wrote in message
...

kjpro @ usenet.com wrote:


"CJT" wrote in message
...



FWIW, our peak day this year was August 12. Our AC ran for 11 hours
40
minutes.



Straight or in a 24 hr period?



In a 24 hour period, midnight to midnight.



I hope that wasn't at design temperature.


Whatever design parameters were used 25 years ago when the house was
built have been forgotten long ago. And the original designer couldn't
have known what temperature profile I would now set in my programmable
thermostat (especially since I don't think such thermostats were even
on the market yet back then), nor could (s)he have known that I would
have installed a radiant barrier in my attic, nor many other factors
that affect the AC load. So there's really not much sense in discussing
whether the peak day this year was at "design temperature" or not. In
fact, one might argue that design by rule can't hope to get very close
to the "right" answer, particularly when load patterns can change over
time (e.g. I could install more insulation or the insulation I have
could compact and lose its effectiveness, I could throw more/fewer
parties with lots of heat-exhaling guests, global warming could affect
the climate, I could plant trees which over time could mature and shade
the house, I could install blinds and draperies, I could paint the
house a different color and install a different color roof, etc.).


Geez.... 25 years old, replace that old energy hog!

"CJT" wrote in message
...
Jud McCranie wrote:
On Wed, 19 Sep 2007 01:40:52 GMT, Robert Allison
wrote:


Your real estate agent also does air conditioning?

Let the HVAC guys size your unit.


Thanks for the recommendation of the chart.

It is hard for me to trust HVAC people on such matters. Last year my
parents got new units for two houses. One has two stories, six
bedrooms, 5.5 baths, and seven other rooms and they sized it at 2
tons. Now the inside of their house is mildewing because it can't
keep it cool or dry. The other house is one small story, three
bedrooms, two baths, 2 other rooms, and they (different person) sized
it at 4 tons. I told my parents that, if anything, they should have
put the 4 ton unit in the big house and the 2 ton unit in the small
house.

All you need to do is hang around here for a while (or, better still,
alt.hvac) to know that there are plenty of alleged "professionals" in
the business who don't know squat.


Na... you're doing just fine!

On Tue, 18 Sep 2007 19:47:04 -0400, Jud McCranie
wrote:

I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.

This is for cooling only, but you can approximate the heating.

http://www.hvacopcost.com/


The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.

Maybe, need a load study by a qualified HVAC person.


I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.



There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.

You used nothing in November? where do you live, Key West.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?


I was faced with the decision about 18 months ago when the compressor
in my 16 year old unit went out. New compressor or new unit. HVAC
guy talked me into new unit. Said savings would be significant. I'm
glad I listened to him. I'm all electric and have a 5 ton packaged
unit and my total usage went down by approximately 20%. I've never
had an August as hot as '07 (20 days over 100F, most lows high 70's
to low 80's) and my bill was $192. The previous five Augusts averaged
about $250. Plus the new unit is far more quiet.

I went from an estimated 7 SEER (I guess that long ago they were not
labeled), to a 13 SEER

If you are in the U. S. and pay taxes, you should also go on the gov.
energy site and look up the potential tax credits. I believe it is
$300 for a heat pump that meets the SEER and EER, and the standard for
the heat side, requirements.

In my case the difference between a new compressor and a new unit was
$3K. I couldn't qualify for the tax credit, because, low and behold,
there was no "packaged" unit in existence that met the Govs standards
on the heat side. But there were plenty of splits which are more
common. You can get a split up to 19 SEER. I figure I'm saving about
$4-500 per year. So six years or so simple payback without the tax
credit.

Frank

kjpro @ usenet.com wrote:
"CJT" wrote in message
...

kjpro @ usenet.com wrote:


"CJT" wrote in message
...


kjpro @ usenet.com wrote:



"CJT" wrote in message
...




FWIW, our peak day this year was August 12. Our AC ran for 11 hours

40

minutes.



Straight or in a 24 hr period?



In a 24 hour period, midnight to midnight.



I hope that wasn't at design temperature.



Whatever design parameters were used 25 years ago when the house was
built have been forgotten long ago. And the original designer couldn't
have known what temperature profile I would now set in my programmable
thermostat (especially since I don't think such thermostats were even
on the market yet back then), nor could (s)he have known that I would
have installed a radiant barrier in my attic, nor many other factors
that affect the AC load. So there's really not much sense in discussing
whether the peak day this year was at "design temperature" or not. In
fact, one might argue that design by rule can't hope to get very close
to the "right" answer, particularly when load patterns can change over
time (e.g. I could install more insulation or the insulation I have
could compact and lose its effectiveness, I could throw more/fewer
parties with lots of heat-exhaling guests, global warming could affect
the climate, I could plant trees which over time could mature and shade
the house, I could install blinds and draperies, I could paint the
house a different color and install a different color roof, etc.).



Geez.... 25 years old, replace that old energy hog!


Replacing it would be uneconomical.

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

Frank Boettcher wrote:

On Tue, 18 Sep 2007 19:47:04 -0400, Jud McCranie
wrote:


I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.


This is for cooling only, but you can approximate the heating.

http://www.hvacopcost.com/


The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.


Maybe, need a load study by a qualified HVAC person.


I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.



There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.


You used nothing in November? where do you live, Key West.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?



I was faced with the decision about 18 months ago when the compressor
in my 16 year old unit went out. New compressor or new unit. HVAC
guy talked me into new unit. Said savings would be significant. I'm
glad I listened to him. I'm all electric and have a 5 ton packaged
unit and my total usage went down by approximately 20%. I've never
had an August as hot as '07 (20 days over 100F, most lows high 70's
to low 80's) and my bill was $192. The previous five Augusts averaged
about $250. Plus the new unit is far more quiet.

I went from an estimated 7 SEER (I guess that long ago they were not
labeled), to a 13 SEER

If you are in the U. S. and pay taxes, you should also go on the gov.
energy site and look up the potential tax credits. I believe it is
$300 for a heat pump that meets the SEER and EER, and the standard for
the heat side, requirements.

In my case the difference between a new compressor and a new unit was
$3K. I couldn't qualify for the tax credit, because, low and behold,
there was no "packaged" unit in existence that met the Govs standards
on the heat side. But there were plenty of splits which are more
common. You can get a split up to 19 SEER. I figure I'm saving about
$4-500 per year. So six years or so simple payback without the tax
credit.

Frank

That's not how you should calculate payback. Consider the interest
on that $3K if you hadn't sunk it into the AC.

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

On Fri, 21 Sep 2007 21:00:33 -0500, CJT wrote:

Frank Boettcher wrote:

On Tue, 18 Sep 2007 19:47:04 -0400, Jud McCranie
wrote:


I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.


This is for cooling only, but you can approximate the heating.

http://www.hvacopcost.com/


The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.


Maybe, need a load study by a qualified HVAC person.


I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.



There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.


You used nothing in November? where do you live, Key West.

Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?



I was faced with the decision about 18 months ago when the compressor
in my 16 year old unit went out. New compressor or new unit. HVAC
guy talked me into new unit. Said savings would be significant. I'm
glad I listened to him. I'm all electric and have a 5 ton packaged
unit and my total usage went down by approximately 20%. I've never
had an August as hot as '07 (20 days over 100F, most lows high 70's
to low 80's) and my bill was $192. The previous five Augusts averaged
about $250. Plus the new unit is far more quiet.

I went from an estimated 7 SEER (I guess that long ago they were not
labeled), to a 13 SEER

If you are in the U. S. and pay taxes, you should also go on the gov.
energy site and look up the potential tax credits. I believe it is
$300 for a heat pump that meets the SEER and EER, and the standard for
the heat side, requirements.

In my case the difference between a new compressor and a new unit was
$3K. I couldn't qualify for the tax credit, because, low and behold,
there was no "packaged" unit in existence that met the Govs standards
on the heat side. But there were plenty of splits which are more
common. You can get a split up to 19 SEER. I figure I'm saving about
$4-500 per year. So six years or so simple payback without the tax
credit.

Frank

That's not how you should calculate payback. Consider the interest
on that $3K if you hadn't sunk it into the AC.

If you read carefully I said "simple" payback, not payback based on
discounted cash flow or present value analysis.

So are you suggesting that at the decision point of whether to sink
$1000 into a sixteen year old, inefficient heat pump that would
require maintenance money put into it each year despite the new
compressor, that I should have considered that a reasonable
alternative? Maintenance money combined with unit inflation till the
time when it would have to be replaced anyway which would be far in
excess of the interest earned on the savings? True discounted cash
flow considers both the timing and amount of both outlays and income.

If you assign risk appropriately and run all the numbers, the decision
is a no brainer


Frank

Frank Boettcher wrote:

On Fri, 21 Sep 2007 21:00:33 -0500, CJT wrote:


Frank Boettcher wrote:


On Tue, 18 Sep 2007 19:47:04 -0400, Jud McCranie
wrote:



I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.


This is for cooling only, but you can approximate the heating.

http://www.hvacopcost.com/



The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.


Maybe, need a load study by a qualified HVAC person.



I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.



There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.


You used nothing in November? where do you live, Key West.


Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?



I was faced with the decision about 18 months ago when the compressor
in my 16 year old unit went out. New compressor or new unit. HVAC
guy talked me into new unit. Said savings would be significant. I'm
glad I listened to him. I'm all electric and have a 5 ton packaged
unit and my total usage went down by approximately 20%. I've never
had an August as hot as '07 (20 days over 100F, most lows high 70's
to low 80's) and my bill was $192. The previous five Augusts averaged
about $250. Plus the new unit is far more quiet.

I went from an estimated 7 SEER (I guess that long ago they were not
labeled), to a 13 SEER

If you are in the U. S. and pay taxes, you should also go on the gov.
energy site and look up the potential tax credits. I believe it is
$300 for a heat pump that meets the SEER and EER, and the standard for
the heat side, requirements.

In my case the difference between a new compressor and a new unit was
$3K. I couldn't qualify for the tax credit, because, low and behold,
there was no "packaged" unit in existence that met the Govs standards
on the heat side. But there were plenty of splits which are more
common. You can get a split up to 19 SEER. I figure I'm saving about
$4-500 per year. So six years or so simple payback without the tax
credit.

Frank


That's not how you should calculate payback. Consider the interest
on that $3K if you hadn't sunk it into the AC.


If you read carefully I said "simple" payback, not payback based on
discounted cash flow or present value analysis.

So are you suggesting that at the decision point of whether to sink
$1000 into a sixteen year old, inefficient heat pump that would
require maintenance money put into it each year despite the new
compressor, that I should have considered that a reasonable
alternative? Maintenance money combined with unit inflation till the
time when it would have to be replaced anyway which would be far in
excess of the interest earned on the savings? True discounted cash
flow considers both the timing and amount of both outlays and income.

If you assign risk appropriately and run all the numbers, the decision
is a no brainer


Frank


On the facts you presented, you would have had a new compressor.
It's not clear to me why you assume maintenance would be so high.

But my point was just that "simple payback" doesn't tell the
whole picture -- if you actually did the full analysis, then
good for you.

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

On Sat, 22 Sep 2007 17:06:40 -0500, CJT wrote:

Frank Boettcher wrote:

On Fri, 21 Sep 2007 21:00:33 -0500, CJT wrote:


Frank Boettcher wrote:


On Tue, 18 Sep 2007 19:47:04 -0400, Jud McCranie
wrote:



I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.


This is for cooling only, but you can approximate the heating.

http://www.hvacopcost.com/



The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.


Maybe, need a load study by a qualified HVAC person.



I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.



There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.


You used nothing in November? where do you live, Key West.


Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?



I was faced with the decision about 18 months ago when the compressor
in my 16 year old unit went out. New compressor or new unit. HVAC
guy talked me into new unit. Said savings would be significant. I'm
glad I listened to him. I'm all electric and have a 5 ton packaged
unit and my total usage went down by approximately 20%. I've never
had an August as hot as '07 (20 days over 100F, most lows high 70's
to low 80's) and my bill was $192. The previous five Augusts averaged
about $250. Plus the new unit is far more quiet.

I went from an estimated 7 SEER (I guess that long ago they were not
labeled), to a 13 SEER

If you are in the U. S. and pay taxes, you should also go on the gov.
energy site and look up the potential tax credits. I believe it is
$300 for a heat pump that meets the SEER and EER, and the standard for
the heat side, requirements.

In my case the difference between a new compressor and a new unit was
$3K. I couldn't qualify for the tax credit, because, low and behold,
there was no "packaged" unit in existence that met the Govs standards
on the heat side. But there were plenty of splits which are more
common. You can get a split up to 19 SEER. I figure I'm saving about
$4-500 per year. So six years or so simple payback without the tax
credit.

Frank


That's not how you should calculate payback. Consider the interest
on that $3K if you hadn't sunk it into the AC.


If you read carefully I said "simple" payback, not payback based on
discounted cash flow or present value analysis.

So are you suggesting that at the decision point of whether to sink
$1000 into a sixteen year old, inefficient heat pump that would
require maintenance money put into it each year despite the new
compressor, that I should have considered that a reasonable
alternative? Maintenance money combined with unit inflation till the
time when it would have to be replaced anyway which would be far in
excess of the interest earned on the savings? True discounted cash
flow considers both the timing and amount of both outlays and income.

If you assign risk appropriately and run all the numbers, the decision
is a no brainer


Frank


On the facts you presented, you would have had a new compressor.
It's not clear to me why you assume maintenance would be so high.

If you can't understand "16 year old heat pump", a fact that was
clearly presented, and can't project what that means, then I can't
help you.

But my point was just that "simple payback" doesn't tell the
whole picture -- if you actually did the full analysis, then
good for you.

Frank Boettcher wrote:

On Sat, 22 Sep 2007 17:06:40 -0500, CJT wrote:


Frank Boettcher wrote:


On Fri, 21 Sep 2007 21:00:33 -0500, CJT wrote:



Frank Boettcher wrote:



On Tue, 18 Sep 2007 19:47:04 -0400, Jud McCranie
wrote:




I'm trying to estimate how long it would take to recoup my investment
if I buy a more efficient heat pump.


This is for cooling only, but you can approximate the heating.

http://www.hvacopcost.com/




The one we have is 11 years old and has a SEER of 10.05. It is a
4-ton unit for about 1975 square feet and the real estate agent said
that it was oversized, so me might could use a smaller one.


Maybe, need a load study by a qualified HVAC person.




I got my monthly electric bills for the past 12 months. We used a
total of 27,100 kWh, at a cost of $2,574. Our rate depends on the
season and also on how much you use in a month. Summer rates are
higher, and the more you use, the more it cost.



There are periods in the fall and spring where very little heating and
cooling is used. Our smallest bill was in November, using 1600 kWh,
at a cost of $129. If I assumed that this used no heat/cooling, that
means that heating and cooling came to 7,900 kWh, or $1026.


You used nothing in November? where do you live, Key West.



Does that look like I could recoup my investment in a more efficient
heat pump in, say, five years?



I was faced with the decision about 18 months ago when the compressor
in my 16 year old unit went out. New compressor or new unit. HVAC
guy talked me into new unit. Said savings would be significant. I'm
glad I listened to him. I'm all electric and have a 5 ton packaged
unit and my total usage went down by approximately 20%. I've never
had an August as hot as '07 (20 days over 100F, most lows high 70's
to low 80's) and my bill was $192. The previous five Augusts averaged
about $250. Plus the new unit is far more quiet.

I went from an estimated 7 SEER (I guess that long ago they were not
labeled), to a 13 SEER

If you are in the U. S. and pay taxes, you should also go on the gov.
energy site and look up the potential tax credits. I believe it is
$300 for a heat pump that meets the SEER and EER, and the standard for
the heat side, requirements.

In my case the difference between a new compressor and a new unit was
$3K. I couldn't qualify for the tax credit, because, low and behold,
there was no "packaged" unit in existence that met the Govs standards
on the heat side. But there were plenty of splits which are more
common. You can get a split up to 19 SEER. I figure I'm saving about
$4-500 per year. So six years or so simple payback without the tax
credit.

Frank


That's not how you should calculate payback. Consider the interest
on that $3K if you hadn't sunk it into the AC.


If you read carefully I said "simple" payback, not payback based on
discounted cash flow or present value analysis.

So are you suggesting that at the decision point of whether to sink
$1000 into a sixteen year old, inefficient heat pump that would
require maintenance money put into it each year despite the new
compressor, that I should have considered that a reasonable
alternative? Maintenance money combined with unit inflation till the
time when it would have to be replaced anyway which would be far in
excess of the interest earned on the savings? True discounted cash
flow considers both the timing and amount of both outlays and income.

If you assign risk appropriately and run all the numbers, the decision
is a no brainer


Frank



On the facts you presented, you would have had a new compressor.
It's not clear to me why you assume maintenance would be so high.


If you can't understand "16 year old heat pump", a fact that was
clearly presented, and can't project what that means, then I can't
help you.


Without more, it doesn't mean the parts other than the compressor
are about to require lots of maintenance.

But my point was just that "simple payback" doesn't tell the
whole picture -- if you actually did the full analysis, then
good for you.




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

"CJT" wrote in message
...
kjpro @ usenet.com wrote:
"CJT" wrote in message
...

kjpro @ usenet.com wrote:


"CJT" wrote in message
...


kjpro @ usenet.com wrote:



"CJT" wrote in message
...




FWIW, our peak day this year was August 12. Our AC ran for 11 hours

40

minutes.



Straight or in a 24 hr period?



In a 24 hour period, midnight to midnight.



I hope that wasn't at design temperature.



Whatever design parameters were used 25 years ago when the house was
built have been forgotten long ago. And the original designer couldn't
have known what temperature profile I would now set in my programmable
thermostat (especially since I don't think such thermostats were even
on the market yet back then), nor could (s)he have known that I would
have installed a radiant barrier in my attic, nor many other factors
that affect the AC load. So there's really not much sense in discussing
whether the peak day this year was at "design temperature" or not. In
fact, one might argue that design by rule can't hope to get very close
to the "right" answer, particularly when load patterns can change over
time (e.g. I could install more insulation or the insulation I have
could compact and lose its effectiveness, I could throw more/fewer
parties with lots of heat-exhaling guests, global warming could affect
the climate, I could plant trees which over time could mature and shade
the house, I could install blinds and draperies, I could paint the
house a different color and install a different color roof, etc.).



Geez.... 25 years old, replace that old energy hog!


Replacing it would be uneconomical.


Not likely.

kjpro @ usenet.com wrote:
"CJT" wrote in message
...

kjpro @ usenet.com wrote:

"CJT" wrote in message
...


kjpro @ usenet.com wrote:



"CJT" wrote in message
...



kjpro @ usenet.com wrote:




"CJT" wrote in message
...





FWIW, our peak day this year was August 12. Our AC ran for 11 hours

40


minutes.



Straight or in a 24 hr period?



In a 24 hour period, midnight to midnight.



I hope that wasn't at design temperature.



Whatever design parameters were used 25 years ago when the house was
built have been forgotten long ago. And the original designer couldn't
have known what temperature profile I would now set in my programmable
thermostat (especially since I don't think such thermostats were even
on the market yet back then), nor could (s)he have known that I would
have installed a radiant barrier in my attic, nor many other factors
that affect the AC load. So there's really not much sense in discussing
whether the peak day this year was at "design temperature" or not. In
fact, one might argue that design by rule can't hope to get very close
to the "right" answer, particularly when load patterns can change over
time (e.g. I could install more insulation or the insulation I have
could compact and lose its effectiveness, I could throw more/fewer
parties with lots of heat-exhaling guests, global warming could affect
the climate, I could plant trees which over time could mature and shade
the house, I could install blinds and draperies, I could paint the
house a different color and install a different color roof, etc.).



Geez.... 25 years old, replace that old energy hog!



Replacing it would be uneconomical.



Not likely.


like you would have a clue

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

"CJT" wrote in message
...
kjpro @ usenet.com wrote:
"CJT" wrote in message
...

kjpro @ usenet.com wrote:

"CJT" wrote in message
...


kjpro @ usenet.com wrote:



"CJT" wrote in message
...



kjpro @ usenet.com wrote:




"CJT" wrote in message
...





FWIW, our peak day this year was August 12. Our AC ran for 11
hours

40


minutes.



Straight or in a 24 hr period?



In a 24 hour period, midnight to midnight.



I hope that wasn't at design temperature.



Whatever design parameters were used 25 years ago when the house was
built have been forgotten long ago. And the original designer
couldn't
have known what temperature profile I would now set in my programmable
thermostat (especially since I don't think such thermostats were even
on the market yet back then), nor could (s)he have known that I would
have installed a radiant barrier in my attic, nor many other factors
that affect the AC load. So there's really not much sense in
discussing
whether the peak day this year was at "design temperature" or not. In
fact, one might argue that design by rule can't hope to get very close
to the "right" answer, particularly when load patterns can change over
time (e.g. I could install more insulation or the insulation I have
could compact and lose its effectiveness, I could throw more/fewer
parties with lots of heat-exhaling guests, global warming could affect
the climate, I could plant trees which over time could mature and
shade
the house, I could install blinds and draperies, I could paint the
house a different color and install a different color roof, etc.).



Geez.... 25 years old, replace that old energy hog!



Replacing it would be uneconomical.



Not likely.


like you would have a clue


You sure don't.

kjpro @ usenet.com wrote:
"CJT" wrote in message
...

kjpro @ usenet.com wrote:

"CJT" wrote in message
...


kjpro @ usenet.com wrote:


"CJT" wrote in message
...



kjpro @ usenet.com wrote:




"CJT" wrote in message
...




kjpro @ usenet.com wrote:





"CJT" wrote in message
...






FWIW, our peak day this year was August 12. Our AC ran for 11

hours

40



minutes.



Straight or in a 24 hr period?



In a 24 hour period, midnight to midnight.



I hope that wasn't at design temperature.



Whatever design parameters were used 25 years ago when the house was
built have been forgotten long ago. And the original designer

couldn't

have known what temperature profile I would now set in my programmable
thermostat (especially since I don't think such thermostats were even
on the market yet back then), nor could (s)he have known that I would
have installed a radiant barrier in my attic, nor many other factors
that affect the AC load. So there's really not much sense in

discussing

whether the peak day this year was at "design temperature" or not. In
fact, one might argue that design by rule can't hope to get very close
to the "right" answer, particularly when load patterns can change over
time (e.g. I could install more insulation or the insulation I have
could compact and lose its effectiveness, I could throw more/fewer
parties with lots of heat-exhaling guests, global warming could affect
the climate, I could plant trees which over time could mature and

shade

the house, I could install blinds and draperies, I could paint the
house a different color and install a different color roof, etc.).



Geez.... 25 years old, replace that old energy hog!



Replacing it would be uneconomical.



Not likely.



like you would have a clue



You sure don't.



???

You're talking some real nonsense, boy.

I know a lot more about what it costs to run my AC than you do.

And I question the value of any economic analysis you do _without_ that
information.

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

"CJT" wrote in message
...
kjpro @ usenet.com wrote:
"CJT" wrote in message
...

kjpro @ usenet.com wrote:

"CJT" wrote in message
...


kjpro @ usenet.com wrote:


"CJT" wrote in message
...



kjpro @ usenet.com wrote:




"CJT" wrote in message
...




kjpro @ usenet.com wrote:





"CJT" wrote in message
...






FWIW, our peak day this year was August 12. Our AC ran for 11

hours

40



minutes.



Straight or in a 24 hr period?



In a 24 hour period, midnight to midnight.



I hope that wasn't at design temperature.



Whatever design parameters were used 25 years ago when the house was
built have been forgotten long ago. And the original designer

couldn't

have known what temperature profile I would now set in my
programmable
thermostat (especially since I don't think such thermostats were
even
on the market yet back then), nor could (s)he have known that I
would
have installed a radiant barrier in my attic, nor many other factors
that affect the AC load. So there's really not much sense in

discussing

whether the peak day this year was at "design temperature" or not.
In
fact, one might argue that design by rule can't hope to get very
close
to the "right" answer, particularly when load patterns can change
over
time (e.g. I could install more insulation or the insulation I have
could compact and lose its effectiveness, I could throw more/fewer
parties with lots of heat-exhaling guests, global warming could
affect
the climate, I could plant trees which over time could mature and

shade

the house, I could install blinds and draperies, I could paint the
house a different color and install a different color roof, etc.).



Geez.... 25 years old, replace that old energy hog!



Replacing it would be uneconomical.



Not likely.



like you would have a clue



You sure don't.



???

You're talking some real nonsense, boy.


Boy, if you see a boy, you must be looking in a mirror.


I know a lot more about what it costs to run my AC than you do.


I know *a lot* more about properly sized units that save on operational
costs.
Which is what you lack.


And I question the value of any economic analysis you do _without_ that
information.


A moron would question facts.
Why, cause their not smart enough to understand the details.

kjpro @ usenet.com wrote:

snip



I know *a lot* more about properly sized units that save on operational
costs.
Which is what you lack.


snip

A moron would question facts.
Why, cause their not smart enough to understand the details.



Having read what you've written, I'm convinced you know squat.

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

"CJT" wrote in message
...
kjpro @ usenet.com wrote:

snip



I know *a lot* more about properly sized units that save on operational
costs.
Which is what you lack.


snip

A moron would question facts.
Why, cause their not smart enough to understand the details.



Having read what you've written, I'm convinced you know squat.


Don't know her, but I do understand that you know very little about HVAC.