PrecisionMachinisT wrote:
p j m@see _my _sig _for_address.com wrote in message
...

Given 2 identical houses, side by side, one with a 3 ton heat
pump and one with a 10 ton heat pump, the outdoor temperature where
the 3 ton can 'barely keep up' will be very different ( higher )
than
the temperature whre the 10 ton system can barely keep up.

In either event, below the 'thermal balance point', the heat
pump is STILL putting out economical heat into the house, it simply
needs another source to add MORE heat.


IOW, on heating...for the most part, the steep drop-off is in
*capacity*,
not *efficiency* when the outdoor ambient temp swings low.....

Why is this difficult for so many folks ???

Would you guys say that if a HP system is oversized, the COP can fall
enough that the economic balance point is reached, even though the
reduction in capacity isn't enough to hit the thermal balance point?

%mod%