Auxiliary heat
 

Anybody know why my heat pump is doing auxiliary heat past couple of days. Seems to blow cool air when say heat is on and if I turn up the thermostat it changes to auxiliary heat

The auxiliary heater works in conjunction with your HVAC system to keep your home warm when the outside temperature is too cold for the heat pump system to be efficient on its own. The thermostat automatically activates the auxiliary heating when the desired temperature is not met by the heat pump system alone.

After some period of your thermostat not reaching the set temperature, your thermostat automatically activates the auxiliary heat.

The auxiliary heat will only shut off once the thermostat has reached set temperature.

What is Aux Heat? Everything to Know About Auxiliary Heat

100% correct. Something else I do when it gets cold like this and the heat pump is struggling is to put a pot of water on our gas stovetop and boil it for a bit. Puts both heat and humidity into the house and gets the house warmer quicker on a cold morning before the sun comes up.

ALTAVIA is spot on…I also would have your AC/ Heat pump checked for Proper Charge… we got cold but your Heat Pump should have kept up with it..( also depends on your settings)

I agree. It really hasn't been cold enough for the electric heat coil to come on.

My unit is newer and I just had it serviced, and my electric heat coil came on. Heat pumps, at least the ones the builder installs, struggle once temps go below about 40 degrees. And if you set back your thermostat at night (like I do) and it is having to raise the temp vs just maintain, it will have to work even harder.

We have had no problems with the builder installed (2013 vintage) Carrier HVAC system, and we have never had the emergency heat come on. I am not an HVAC expert and I do not have any equipment to check the system, so I would suggest having the system checked again.
One other thought, if your temperature change is large enough this may be causing the emergency heat to come on. We keep the temp more or less the same between night and day, and just use a fan if it is too warm at night.

Same here. Set to 65 and heat never came on. Benefit of block construction

AS VT state,d keeping a constant heat setpoint helps to minimize the need for the aux heating to come on during normal heat mode.

See Altavia post #3 for a link to a good description of auxiliary heating uses in a heat pump system.

IMHO, ALL heat pumps struggle when temperatures are below 40F since the heat pump is using a reverse air conditioning cycle to take heat from the outside air and eject it to the inside air and actually heating it. The cooling occurring at the outside condenser now acting as an evaporator now causes water in the outside air to freeze on the coils. The HVAC system senses this and goes into defrost mode.
1. The system goes back to AC.
2. Warm inside air now goes through the inside heat exchanger and evaporates the refrigerant.
3. The refrigerant vapor gets compressed in the outside compressor and increases in temperature.
4 The hot refrigerant vapor now goes to the condenser and rejects heat to the coil and melts the ice/frost.
5. The auxiliary heater now comes on to avoid cooling the air inside the house.
6. When defrosting complete, the system goes back to the original heating using the heat pump.

A perhaps better idea. Make some soup.

These haven’t been cold temperatures that would have caused any aux heating issues. There are multiple variants of furnaces and heat pumps and we in the villages have the simple/less efficient 1’s installed (not talking about the seer rating, I’m talking about single stage vs. multi stage setups). I had a heat pump installed in my home in snow country that was beneficial down to 0 degrees and this setup was a multistage configuration where it operated efficiently at low temps by using more and more of the furnace as the temps dropped (stages) instead of the units coming on all at once say at 30 degrees.

Aux heat comes on when then the thermostat is set for three or more degrees increase in heat.

Why waste your time on this site posting a comment that is of no help and yes, actually there are experts on this site

always the typical "why ask here" response from mkjelenbaas -you can count on it-

It’s a shame that some just like to post nonsense instead of actually helping. Hopefully you get a resolution to your question or at least get you going in the right direction.

You mentioned you set-back the heat. This is why your Aux-Heat came on. The system is trying to get the house back to the target temperature and the heat pump alone is not generating enough heat to make this happen.

Almost every electronic thermostat i know of has settings to manage when the Aux-Heat comes on. Just google aux heat for your specific thermostat to find out where these settings are.

Also remember when the Aux-Heat comes on the coil in you air handler can draw about 40 amps so if it's on a long time expect a large electric bill.

Normally the Carrier HVAC the builder installed should work fine with the weather here in Central Florida. But it is possible the temperature could drop below the point where the Heat Pump being able to heat your home which is why we have Aux-Heat.

I can tell you 100%, many don't worry about heat because it usually doesn't stay cold (around freezing) for several days here in the Villages. If it ever stayed around freezing for several days the house and the ground underneaith would loose it's heat build up and your heat would be going on a lot.