"AC/DCdude17" wrote in message

How come my A/C struggles to maintain 25°F difference running
continuously whereas my heater can maintain 40°F+ difference without
running continuously even though they both have the same BTU performance?

Both results were with the central HVAC turned off.

You have only once source of heat removal (cooling) with the AC, but you
have many heat sources helping the space heater.

The AC is pulling down the air temperature and heat is still getting into
the room from various sources. The walls not only tot he outside, but to
the rest of the house are transmitting heat into the room. The crack under
the door. Lights, TV, even your body. IIRC, an average adult gives off 400
Btu per hour just sitting in a chair.

The heater is getting help from all of these sources. Daylight hours it is
getting solar heat. While the outside temperature is 30 degrees, what about
the rest of the house? Are all the walls at 30 or are they closer to maybe
60 giving a lesser differential and thus lesser heat loss?

While 5,000 Btu is still 5,000 Btu, the heating and cooling loads are not
necessarily equal in the particular room.
Ed

Edwin Pawlowski wrote:

...While 5,000 Btu is still 5,000 Btu, the heating and cooling loads are not
necessarily equal in the particular room.

And specs for heating equipment are more straightforward than specs
for cooling equipment. An AC may only make 5K Btu/h of cooling under
rare operating conditions.

Nick

AC/DCdude17 writes:

How come my A/C struggles to maintain 25øF difference running
continuously whereas my heater can maintain 40øF+ difference without
running continuously even though they both have the same BTU performance?

Heat load is more than just temperature difference.

"Richard J Kinch" wrote in message
. ..
AC/DCdude17 writes:

How come my A/C struggles to maintain 25øF difference running
continuously whereas my heater can maintain 40øF+ difference without
running continuously even though they both have the same BTU
performance?

Heat load is more than just temperature difference.

Only sorta slightly related, but Im running a water source heat pump,
cooling house and heating swimming pool concurrently......

Water flow rate is ~7 gpm, incoming water is at 84 deg F, outgoing at 96 deg
F--so I'm figuring it's moving roughly 40,320 btu of heat--this is a 3-1/2
ton unit.......

Anyone care to double check my numbers or have any questions / comments ???

--

SVL

"PopRivet" wrote in message

Good grief, there are certainly a lot of "logic"
answers here, most with some but not much merit.
Simply stated, it takes a LOT more energy to drop the
temp a degree than to raise the temp a degree, because
of the methodologies. The technology for increasing
temperature is simply much more efficient that that for
lowering the temperature.

Pop

Explain please.

If you have a mass and remove 5,000 Btu or add 5,000 Btu, it is still the
same amount of energy it is still the same mass. Since Btu is really an
expression of Btu PER HOUR, the same amount of energy is being moved in the
same time period.

Take the window AC unit and mount it backwards so it exhausts from the
condensing coil the heat into the room. Would the effect of running it
raise the temperature more or less than a heater that gives of 5,000 Btu of
heat? If two rooms were the same temperature and one had the heater, the
other h ad the AC (assuming the outside air is at the temperature used to
get the 5k rating), which room would be heated more?

"Edwin Pawlowski" wrote in message
m...

"PopRivet" wrote in message

Good grief, there are certainly a lot of "logic"
answers here, most with some but not much merit.
Simply stated, it takes a LOT more energy to drop the
temp a degree than to raise the temp a degree, because
of the methodologies. The technology for increasing
temperature is simply much more efficient that that for
lowering the temperature.

Pop

Explain please.

If you have a mass and remove 5,000 Btu or add 5,000 Btu, it is still the
same amount of energy it is still the same mass. Since Btu is really an
expression of Btu PER HOUR, the same amount of energy is being moved in
the
same time period.

Take the window AC unit and mount it backwards so it exhausts from the
condensing coil the heat into the room. Would the effect of running it
raise the temperature more or less than a heater that gives of 5,000 Btu
of
heat? If two rooms were the same temperature and one had the heater, the
other h ad the AC (assuming the outside air is at the temperature used to
get the 5k rating), which room would be heated more?



Doh!!!

Stop it NOW.................

Your gonna confuse them all with this talk of "btu's"....

--

SVL

Edwin Pawlowski wrote:

"PopRivet" wrote in message

...Simply stated, it takes a LOT more energy to drop the
temp a degree than to raise the temp a degree, because
of the methodologies. The technology for increasing
temperature is simply much more efficient that that for
lowering the temperature.

I'm afraid you are incorrect, Mr. Rivet. Think "COP = 3."

Take the window AC unit and mount it backwards so it exhausts from the
condensing coil the heat into the room.

In wintertime, with the cool side in a damp basement stairwell...

Would the effect of running it raise the temperature more or less than
a heater that gives of 5,000 Btu of heat?

About 30% more than 5000 Btu/h, given compressor and fan motor powers.

Nick

"Edwin Pawlowski" wrote in message
m...

"PopRivet" wrote in message

Good grief, there are certainly a lot of "logic"
answers here, most with some but not much merit.
Simply stated, it takes a LOT more energy to drop the
temp a degree than to raise the temp a degree, because
of the methodologies. The technology for increasing
temperature is simply much more efficient that that for
lowering the temperature.

Pop

Explain please.

If you have a mass and remove 5,000 Btu or add 5,000 Btu,
it is still the
same amount of energy it is still the same mass. Since
Btu is really an
expression of Btu PER HOUR, the same amount of energy is
being moved in the
same time period.

Take the window AC unit and mount it backwards so it
exhausts from the
condensing coil the heat into the room. Would the effect
of running it
raise the temperature more or less than a heater that
gives of 5,000 Btu of
heat? If two rooms were the same temperature and one had
the heater, the
other h ad the AC (assuming the outside air is at the
temperature used to
get the 5k rating), which room would be heated more?


True, but the LOSSES (efficiency) of causing that are
grossly different. Your analogy is sound, but it ignores
the losses involved in makng that change occur, which is
what the OP was asking about. I'm afraid getting into a
technical debate, especially one with the lossless descrip
you're trying to use would be futile and take way too much
ether and time. Keep reading; it's there.

Pop

wrote in message
...
Edwin Pawlowski wrote:

"PopRivet" wrote in message

...Simply stated, it takes a LOT more energy to drop
the
temp a degree than to raise the temp a degree, because
of the methodologies. The technology for increasing
temperature is simply much more efficient that that for
lowering the temperature.

I'm afraid you are incorrect, Mr. Rivet. Think "COP = 3."
=== I'm afraid I don 't understand: After making that
comment, youthen proceed next to agree with it by offering
a related analogy. ?!?


Take the window AC unit and mount it backwards so it
exhausts from the
condensing coil the heat into the room.

In wintertime, with the cool side in a damp basement
stairwell...

Would the effect of running it raise the temperature more
or less than
a heater that gives of 5,000 Btu of heat?

About 30% more than 5000 Btu/h, given compressor and fan
motor powers.

Nick

"Pop Rivet" wrote in message

I'm afraid getting into a
technical debate, especially one with the lossless descrip
you're trying to use would be futile and take way too much
ether and time. Keep reading; it's there.

Pop

I'm not looking to get into a debate, but I'm looking to learn something.
Guess you don't know enough to teach me so I'll look elsewhere. Thanks
anyway.
Ed