Heat Pump Lockout Temp

[woessner]

My wife and I got new HVAC (dual fuel: heat pump + furnace) system back

in July. Now that it's getting cold in Northern Virginia, I'm wondering if I should make any adjustments to the settings. Specifically, the control unit has a cold-lockout temperature for the heat pump. This is the outdoor temperature below which the system will

bypass the heat pump and go directly to the furnace for heat.

So the question is, what (if anything) should I set it to? Is there some sort of rule of thumb?

The heat pump is a Carrier Infinity 17 with an HSPF of 9.5. I looked through all my documentation but didn't find any sort of efficiency graph. I read somewhere that they're sometimes on the unit, itself, perhaps inside the service door.

If anyone has some wisdom to share, I'd sure appreciate it.

Thanks in advance, Bill Woessner

[Andy & Carol]

Up here in Pa., we set ours at 40 degrees, that seems to work out ok here...Andy

[Dr. Hardcrab]

My local co-op electric company (about an hour south of you) says to set them at 35 degrees for the "most economical operation".. Whenever we install them, we set them at 40 and have never had a customer complaint.

BTW, nice system (Infinity)....

[Jim Rusling]

I live in Oklahoma and I have mine set to 36. I have had mine for 9 years and that seems to work pretty good.

[TURTLE]

This is Turtle.

When i install a heat pump and set the outdoor thermostat to switch from the pump to the back up fuel. i set it on or about freezing. so here is a hart for the different people.

Rich and Don't want them to see any difference in the pump or fuel back up. 40 degrees.

Normal people who want to try to save a little money and see about the job being right. 32 degrees.

Poor People that need to save all they can and cut the cost a great deal and don't care about seeing a little difference in the temperature in the house. 20 degrees.

Pick out of the above to see what you want.

TURTLE