What is a heat pump with auxiliary backup heat?

Asked By: Aris Oetges | Last Updated: 4th January, 2020
Category: home and garden indoor environmental quality
4.4/5 (226 Views . 28 Votes)
Without Auxiliary Heat. When outside temperatures drop too low to allow the heat pump to extract heat from the frigid air, some systems switch on a backup heating system to supply the rest of the heat needed to reach the desired temperature inside.

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Considering this, what is auxiliary heat on a heat pump?

Aux on the thermostat stands for auxiliary heat. Auxiliary heat is the electric heat strip in your air handler that is supplemental heat. Auxiliary heat/ Emergency heat help the heat pump keep up when cold outside or the temperature differential on the thermostat is large.

Secondly, what temp should AUX 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.

In respect to this, why does my thermostat say auxiliary heat?

Turning your thermostat to “heat” came with an unexpected “AUX” function appearing. The “AUX Heat” mode is usually an indicator that it's freezing outside, and your is heat pump is using a secondary backup heat source – your auxiliary heat—to keep your home at your set temperature.

What is the difference between auxiliary heat and 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.

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How do I stop my auxiliary heat from coming on?

One of the simplest things you can do to keep your Honeywell thermostat from switching to auxiliary heat is to lower the temperature in your home. Setting the thermostat for somewhere between sixty to sixty-eight degrees is all you should need to do to get the problem under control.

Can I turn off auxiliary heat?

Because auxiliary heat is so expensive, running the heat pump longer can be cheaper than using AUX heat. Heat Pump Balance can automatically turn the heat on early to reduce AUX heat use as much as possible and get to your target temperature on time.

How do you reset your heat pump?

Reset the system by turning it off with the thermostat or breaker if your unit has a safety device locking it out. Wait 60 seconds and turn it back on. It may take up to 10 minutes for the outdoor unit to start.

What does heat on auxiliary mean?

Auxiliary heat is a heating system that works when the temperature inside a home or building drops lower than two or three degrees from what the temperature is set. Or when someone decides they are cold, and turns the thermostat up more than three degrees. Auxiliary heat is a component of heat pump systems.

Why is my heat pump blowing cold air?


You see, a heat pump heats your home by moving heat from the outdoor air into your home. But as it gets colder, and your heat pump can't pull as much heat in from the outdoor air, the air coming from your vents drops slightly in temperature. If so, your heat pump is blowing warm air that just feels cold to you.

Should I leave my heat pump on all the time?

According to Energywise, you shouldn't leave your heat pump on all day. "You should only heat your home when you need it," Hoerning said. "Don't leave your heat pump on all day if you're not there. You can set the timer to turn the unit on half an hour or so before you get home or before you get up in the morning."

Should my heat pump run continuously?

In fact, many heat pumps may run continuously during bitterly cold weather. Believe it or not, a properly sized and installed heat pump should run almost continuously when it is below 30 degrees or so. If you want the fan to run only when there is a need for A/C or Heat, set your thermostat to "AUTO".

What temperature should I set my heat pump in the winter?

Set your thermostat to 68 degrees Fahrenheit in the winter
According to ENERGY STAR, setting your thermostat to 68 degrees Fahrenheit (20 degrees Celsius) when you're home is the ideal balance of comfort and energy efficiency.

Why Does My Honeywell thermostat say auxiliary heat?

"Auxiliary heat" means the secondary heating source. You have the thermostat set to keep your maximum temperature at a certain point, at which the device providing heat turns off. Your thermostat has two possible heat sources, a main and an auxiliary. It depends on how the unit was wired which heat source is which.

How do I reset my thermostat?


Here are the steps you need to take to reset your AC thermostat.
  1. Shut Down Your AC at the Thermostat. The first step in resetting your AC thermostat is to turn it off at the AC unit.
  2. Find Your Circuit Breaker Box.
  3. Reset the Circuit Breaker for Your AC Unit.
  4. Wait 30 Seconds.
  5. Turn the AC Thermostat Back On.

How do you troubleshoot a heat pump?

If the breaker was not tripped, the problem could be the thermostat, low voltage wiring, or the fan relay. If the fan is running, turn the thermostat to emergency heat. Ensure that the setpoint is at least 5 degrees above room temp. Wait for about a minute, then check to see if warm air is coming out the vents.

Is auxiliary heat Expensive?

Auxiliary heat can handle more extreme temperatures since it uses electric heat strips. What this means, unfortunately, is that it's more expensive than the conventional heat provided by a heat pump. While a gas furnace is not as efficient as a heat pump, it is more efficient than a heat pump using auxiliary heat.

Do all heat pumps have auxiliary heat?

In hot weather, heat pumps as air conditioners absorb heat inside a building and discharge it outside. With cold winter temperatures, heat pumps absorb heat outside the building and release it inside. While some heat pumps have that auxiliary heating capability, others do not.

How do I know if my heat pump is working properly?

The fastest way to determine whether you have a heat pump or not is to turn the heat on at your thermostat. Once you feel hot air coming through your vents, walk outside and see if the outdoor unit is running. You see, a heat pump is an air conditioner that can also provide heat during the winter.

Why is my heat pump not blowing hot air?


1) Low refrigerant charge
The heat pump needs refrigerant to transfer heat. Here's the problem: If your heat pump is low on refrigerant, it's having a hard time transferring enough heat into your home to warm the air properly. The fix: Call a heat pump technician to check your refrigerant charge.

Is it normal for AUX heat to come on?

Aux heat should only kick on when the heat pump can't produce enough heat to warm your home on its own. This is typically caused by one of three factors: when it's below 35° outside, you're trying to heat your home by 3° or more, or your heat pump is in defrost mode.

Does the outside unit run when heat is on?

Heat Pump Operation
Therefore, when you run the furnace in the winter, the outside unit should not run as it only functions as part of your air conditioning system. Refrigerant absorbs heat from the outside air and moves it indoors with the help of a reversing valve and multiple check valves.