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RP
 
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Default prog. therm. and heat pump questions



wrote:
RP wrote:


Conventional Heat Pumps get an average COP of 2 to 1...

Thus if the overnight (set back) runtime is reduced by an amount of time
that is twice the recovery time with heat strips enabled), then energy
is saved over not setting back...

Thus? :-)


Thus, yes, at some higher COP and/or warmer climate the trend will reverse.
That's why I said in summary that economy depends upon the system



I don't quite see a "thus" there. Would you further explain your logic?


I'm sorry, that won't be possible. I can however add more conclusions at
will. It's quite easy once you get the hang of it

I'm not in the mood to drag in formulas at this point in time, having
worked all weekend, till dark hours. IOW, I'm too damned tired

You've probably worked through this already, so if you would, could you
please provide some math to analyze the set-back savings of various COP
systems with and without resistance heat enabled?

Without strip heat enabled it *seems* obvious that the monetary savings
of setting back would be greater with the lower COP system. IOW, with a
COP of 1, you have effectively the economy of straight strip heat, in
which case setting back definitely helps the pocket book. OTOH I'd be
very grateful if you could prove otherwise, as my wife is a setting-back
fanatic and I'm tired of waking up to a cold ****er. I suppose I could
shorten it a bit, but hanging it in the water easier than aiming when
you haven't had your coffee yet.

hvacrmedic



Would you agree that night setbacks always save energy if the heat strips are
switched off, even though that may require longer reheating after the setback?

Nick