My new heat pump

[Bird]

Well, I'm still learning, and sure have appreciated the information on TBN. Thursday our heat pump ran continuously from before I got up at 5 a.m. until 1 p.m. Yesterday morning, it ran continuously until about 10 a.m. With outside temperatures of 7 to 14, and the thermostat showing 4 or 5 degrees below what it was set for, I wondered whether the auxilliary heat strip was working. I was only getting 76 to 80 degree air from the registers, but it kept the house reasonably comfortable.

So this morning, it was 24 degrees to start with and had warmed outside to about 32 when I decided to try another little experiment. I raised the thermostat setting to 4 degrees above what it was showing as actual, and switched the thermostat to "EM" (emergency). Wow, the heat pump (outside unit) shut down, the blower picked up speed and the air coming from the nearest register was 104. /forums/images/graemlins/shocked.gif Probably nearly spun the electric meter off the side of the house, but I'll bet that would warm things up in a hurry if necessary.

The manual for this programmable thermostat has instructions for wiring, testing, settings, etc. but says absolutely nothing about what that "EM" setting is for. I just learned that here on TBN.

 

[techman]

The outside unit should not have shut down when the electric strip heat comes on. They are intended to supplement the output from the heat pump, not replace it. Only when you switch the stat to Emergency should you have only electric strip heat.

It is most likely wiring or a setting in a digital thermostst.

paul

 

[Bird]

Yeah, Paul, I think it's the way the digital programmable thermostat is wired. On the "heat" setting; i.e., the normal setting, the heat pump runs and the auxilliary heat strip supplements it. It was in another thread that someone told us that the "EM" (emergency) setting is actually for use in the event that the heat pump becomes non-functional so you still have heat. I had never seen a thermostat before with 4 positions on the switch: cool, off, heat, EM, so I wanted to see if it actually worked. It not only works but got hotter than with the heat pump running which really surprised me.