Should auxiliary heat come on?
Furthermore, at what temperature should auxiliary heat come on?
Auxiliary Heat. Auixiliary Heat will turn on automatically when heat can no longer efficiently transfer heat from the outside air to heat pump. This is when the outside is around 35-40 degrees and the indoor temperature is around three degrees cooler than the thermostat setting.
Secondly, is auxiliary heat the same as emergency heat? I guess the only difference is that AUX is an 'indicator' on your thermostat that you are running the heat strips when the switch is set to HEAT. Emergency Heat is just the switch setting that will turn off the heat pump and only run the auxiliary heat. Emergency Heat Indicator only when in Em. Heat Mode.
Keeping this in consideration, how do I stop my auxiliary heat from coming on?
To limit auxiliary heat and lower your heating costs, a critical first step is to set a lower indoor temperature. If it's 30 degrees outside, it is unreasonable to expect the system to maintain an indoor temperature of 78 without using the heat strips.
How much more expensive is auxiliary heat?
As we mentioned above, AUX heat usually costs up to 50% more than heat transfer, which means if your system is running on AUX heat when it shouldn't be, your heating bill is likely going to be a lot higher than you'd like it to be.