[Shop-talk] Heat pump night setback

[David C.]

We just had a heat pump system installed to replace our propane furnace.
  We had no A/C before, either.  We kept the propane for emergency heat.
  My question is how low can you set the night setback and still have a
reasonable recovery in the morning.  Right now I have it set for 69*
heating and 65* on night setback in the heating mode.  Night SB kicks in
at midnight, back up at 8:00 AM.  I'm not going to worry about the A/C
part until next summer.

The problem is my wife has been told by apparently "several people" that
any more than a 4 degree night setback will cause the compressor to run
excessively the next day to bring the heat back up, wiping out most of
the energy savings from setting the temperature back.  Frankly, this
sounds like BS to me, but I thought I would get some other opinions from
people who have BTDT.  I would prefer about an 8 to 10 degree setback,
but if 4 is the most recommended, I guess it's better than nothing.

Thanks
Dave