What is auxiliary heat

What is Auxiliary heat? When your system reverses to thaw the coils, the radiation strips automatically turn on to keep your home warm. This is referred to as “auxiliary heat.” This is usually not controllable manually but is switched on automatically when your system detects that it has been running for too long.

Axillary heat

What is a Thermostat’s Auxiliary Heat?

Auxiliary heating goes in when the temperature inside your home drops two or three degrees below the temperature set on the thermostat to help warm your home faster. Unless you check your thermostat and see that the “AUX” light is switched on, you won’t notice the switch has occurred most of the time.

Depending on whether your home utilizes a

1. Honeywell thermostat
2. Nest thermostat
3. Another form of a smart thermostat

The aux heat indicator on your thermostat will light up or begin flashing for some time, alerting you. Because your thermostat activates supplemental heat when the temperature inside your home falls below the desired temperature you’ve selected.

This happens when the indoor temperature on your thermostat falls below the predetermined indoor environment temperature by 2-3 degrees. Once your residence reaches the thermostat set point, the auxiliary heat will switch off.

How a Heat Pump Works––A Quick Refresher

First and foremost, it’s critical to comprehend. Before you can answer the question above, you must first understand how a heat pump works. A heat pump differs from a furnace in that it transfers heat from one location to another rather than producing it.

It works in the opposite direction as an air conditioner. When it’s working as an air conditioner for your home, it draws heat in from the outside and moves it inside, then does the opposite with cold air––it removes heat from within and moves it outside.

There are two main reasons for the energization of this setting:

Heat Pumps Aren’t Capable of Producing Enough Heat

We all need a jolt of energy now and again to help us achieve our objectives. That’s exactly what your heat pump system’s auxiliary heating setting performs.

In other words, if your heat pump is having trouble maintaining its set temperature, Your heat pump will get a boost from your extra heat. When your heat pump is unable to adequately heat your home, the auxiliary heat will be activated.

In most cases, your heat pump will turn on the auxiliary heat strip inside your secondary heating source to assist it to achieve its specified temperature more quickly. If the light is illuminated, your heat pump’s electric resistance heating has been turned on.

“Defrost Mode” is active on your system.

Is there ice forming on your heat pump? If ice forms on the exterior unit of your heat pump, it will go through a “defrost cycle” to melt it.

The system will use supplemental heat to keep your home warm during this period. When the temperature drops below freezing in the winter, ice can form around the exterior coils. Your heat pump will automatically reverse the refrigerant flow if this occurs. As a result, the hot refrigerant is given to the outdoor unit to aid in the melting of the ice.

During the defrost cycle, your heat pump stops heating your home, forcing some models to automatically switch to aux mode until the defrost procedure is complete.

If your heat pump is in defrost mode, look for the following signs:

  • From the outdoor unit, steam and/or water can be visible.

  • The outside unit’s fan is not working.

  • In some versions, a flashing light on the machine itself indicates that it is in defrost mode.

Emergency Heat vs. Auxiliary Heat

So, how do you tell the difference between auxiliary and emergency heat?

When the external heat pump is too cold to quickly heat your home in freezing weather, the auxiliary heating system will go on. If the temperature lowers rapidly, auxiliary heating kicks in to help heat your home more quickly.

As a result, the hot refrigerant is sent to the outdoor unit to assist in the melting process.

A supplemental heating source is required for heat pumps. When the temperature dips below 40 degrees Fahrenheit, this is very important. The electric resistance heating at the indoor unit, for example, is one of these supplemental heating sources. It can also incorporate backup systems for gas, oil, or even hot water.

“Second-stage” or “back-up” heating refers to these additional heating sources. The heat pump is the “initial state” of heating. When you use your “second-stage” heat without using your “first stage,” you are said to be in an emergency.


A heat pump’s auxiliary heating system is referred to as auxiliary heat on your thermostat. Auxiliary heat is activated when the temperature inside your home falls below-set levels. It works in the same way as an air conditioner to transfer heat from one location to another.

Look for the following signs that your heat pump is in defrost mode: Steam and/or water can be visible, or the outside unit’s fan is not working. Auxiliary heating kicks in to help heat your home more quickly when the temperature drops rapidly.

What is an emergency?

In most cases, your system will need to conduct defrost cycles every few hours when the temperature drops below 40 degrees. Your heat pump, on the other hand, maybe unable to create heat at temperatures in the 20s and 30s or below because there will simply be insufficient heat in the ambient air to extract.

Outside, the refrigerant has gotten so cold that compressing it is practically impossible, and it can’t absorb the remaining heat. In these conditions, running a heater could cause significant damage, so you should turn it off.

The “emergency” heat setting is for situations like this. When you switch it on, your compressor and heat pump turn off completely, and your system’s radiation heat strips turn on. This allows you to keep receiving heat while avoiding damage to your exterior heat pump equipment.

However, keep in mind that you will be expending a significant amount of extra energy in doing so, hence the term “emergency.” To avoid causing damage to your core system, only use this mode when necessary.

Explanation of Emergency Heating

So, when should you turn on the emergency heat? Only use in an emergency!

When something goes wrong with your “first stage” heat, you should utilize emergency heat. Let’s imagine your home isn’t reaching the desired warm temperature since your exterior unit has malfunctioned. After that, you’d put on the emergency heat and phone for help.

The emergency heat setting must be turned on manually and should only be used when the temperature is below 30 degrees. When the heat pump is turned on, it completely shuts down, allowing you to receive heat without causing damage to your external heat pump system.

To avoid causing harm to your central heating system, this should only be used when essential. Having emergency heat on can be more expensive to run, and it will be. This is why it should only be used in an emergency.

How to Turn Off the Auxiliary Heater

When your Honeywell thermostat or any other model thermostat states the auxiliary heat is on, it may appear that it isn’t much you can do. Even this may be too much for your device if the outside conditions are exceptionally cold. To prevent the auxiliary heat from turning on, you may need to make some further alterations to your property.

Learning how to turn off auxiliary heat is a simple process that can help you save money on your heating expenses this winter.

1. Set the heat temperature to a lower level.

Most of the time, the supplemental heat is activated because the home’s temperature is set too high. To maintain a pleasant temperature, you’re pushing your HVAC system to work too hard. To solve the problem, all you need to do is set the thermostat to someplace between 62 and 68 degrees Fahrenheit.

Axillary heat

2. Make Your House More Attractive

Creating a nice, warmer ambiance inside your home is another great strategy to avoid the supplementary heat from running. During the day, open your window shades and let the sun warm your rooms as much as possible. Remember that you may always dress warmly and snuggle up with a warm blanket by layering up.

3. Unused Rooms Should Be Turned Off

Most people have portions of their homes that aren’t used during the day, such as a spare bedroom or a den. Close the doors and close the vents in those rooms to allow the rest of the warm air to be diverted to the rest of your house.

4. The thermostat is set to the Aux Heat setting all of the time.

Some people discover that their thermostat is stuck on aux heat in the thick of winter, or even on a milder winter day. As previously stated, this is due to their HVAC system’s inability to keep up with an acceptable demand for home heating. This is a major problem that should be addressed by a qualified HVAC professional.

Schedule a Heating Tune-Up for the Season

It’s a good idea to have your heating system tested and tuned up before the winter season truly starts. Early autumn is a perfect time to double-check that all of your moving parts are in good working condition, air filters are changed, and your heat source doesn’t need any substantial repairs.


Most of the time, supplemental heat is activated because the home’s temperature is set too high. The emergency setting must be turned on manually and should only be used when the temperature is below 30 degrees. Learning how to turn off auxiliary heat can help you save money on your heating bills.

Take a look at your thermostat.

If you had your heating system serviced in the autumn and the aux heating is still on, it’s possible that your thermostat is to blame. The auxiliary heat may turn on faster with newer thermostats than with older ones. Many modern models will prompt the aux heat setting if the temperature does not rise within the first few minutes.

If you have an outdated thermostat and are having abrupt aux heat overload, It could be due to the model or the fact that it’s time to have an HVAC specialist check at your heat pump. Your heating system could be the source of the problem.

Is it Possible for My Heater to Freeze?

During the winter, though, this cycle might cause frost to form on your exterior coil. Even when the temperature lowers to near-freezing degrees, the refrigerant that reaches your coil is extremely cold, allowing it to find a way to absorb heat.

Even the tiniest amounts of water vapor in the air can condense and freeze in such cold temperatures, resulting in frost on your exterior coil, which can cause the entire heater to freeze over. Yes, as absurd as it may seem, your heater can freeze at temperatures of roughly 40 degrees Fahrenheit or below.

As a result, after a few hours of use, your heater will need to defrost itself to continue working. That implies it must reverse the refrigerant flow to let the hot fluid run through your coil and dissolve any condensed or frozen snow or ice.

But what if you still require warmth?

Simple: during this time, your system activates a series of electrical radiant heat strips, which can still deliver heat but at a higher energy cost.

The operation of these electrical strips is dependent on both “auxiliary” and “emergency” heat. While they allow you to keep getting the heat you need in your house to stay both comfortable and healthy, they are a less ideal option because they cost a lot more to run for longer periods.

Why You Shouldn’t Use Emergency Heat in the First Place (unless you have to)

A Heat Pump System’s outside unit contains components such as a compressor, condensing coil, and valves that efficiently heat or cool your home.

Read this before you turn on your thermostat’s Emergency Heat setting! When the temperature is too low for the heat pump to take heat from outside, typically below 35 degrees Fahrenheit, the Emergency Heat or Auxiliary Heat setting is employed.

Your heating system can then complement the heat with the alternate source, however, if When you put the system on Emergency Heat mode, it becomes the only source of energy, rather than serving its intended purpose.

When you set your thermostat to emergency heat, you risk:

1. Energy bills that are too high

Running your home on Emergency Heat would be prohibitively expensive. When you select this option, your heat is transferred from your heat pump to an electric heat strip, which is substantially less efficient and more expensive.

2. Putting a burden on your system

When you turn on emergency heat, your system bypasses the heat pump and operates as if the main heat source isn’t working at all. This puts a lot of load on the backup element, which is only supposed to be used in extreme situations for a brief time.

When your heating system is working properly, it will use your Emergency Heat when the primary system is unable to control the temperature on its own. maybe your heating system is malfunctioning. Set your thermostat so that the system does not stay on if your fan does not turn on.

Without air circulation, emergency heat might damage your outdoor unit. Unless your heat pump has entirely broken, you should never manually turn on the Emergency Heat. If this is the case, you should get your heating system inspected and fixed as soon as possible.

If you do need to use the Emergency Heat, please contact Wentzel’s and we’ll take care of the problem. Remember, don’t turn on Emergency Heat just because it’s cold outside; do so only if your heat pump isn’t heating your home properly.

When should I turn on my auxiliary heat?

1. When the temperature outdoors falls below 40 degrees.

2. While the defrost cycle is in progress.

3. When the current differs by three degrees or more. • When the thermostat is set to turn on the emergency heat.

I’m not sure how I’ll know if there’s a problem.

1. If the temperature rises above 40 degrees, the auxiliary heat continues to run.

2. The set temperature is not being maintained by the system.

3. Exorbitant electric bills


During the winter, frost might cause frost to form on your heater’s exterior coil. After a few hours of use, your heater will need to defrost itself to continue working. This is referred to as “auxiliary heat,” which is switched on automatically when the temperature inside your home drops below the thermostat.

Scenario 1: Registers Blowing Cool Air

There are two phases of heat in a heat pump. The heat pump is the primary (1st) step. The auxiliary heat (2nd stage) is activated to work in combination with the heat pump if the heat pump is unable to produce enough heat to fulfill the thermostat temperature setting.

The auxiliary heaters have failed to operate in the majority of the “no heat” calls with a heat pump.

If the over-temperature device is activated three times during a run cycle, all new York air handlers have a function that disables the auxiliary heaters. This “lock-out” also energizes the fan, causing it to run indefinitely unless it is manually reset.

Low airflow across the heaters is the most prevalent reason for this failure. A blocked air filter is the most typical reason for limited airflow, although it can also be caused by a dirty interior coil or closed/restricted ductwork.

Reset the lock-out by cycling high-voltage electricity to the lock-out once the source of the airflow restriction has been eliminated.

1. Auxiliary Heater Power Outage

Many air handlers have multiple power breaker circuits. One breaker powers the blower and one heater on an air handler with 15kw heaters, while another breaker powers the remaining two heaters. Look for tripped or turned-off breakers in the breaker panel and on the air handler itself.

2. Issues with Return Ductwork

Even if the heat pump is performing normally if the return duct system has openings or has fallen loose (particularly in an unheated attic or crawlspace), it will take in cold air and give cool air from the supply registers, and the space may not be heated.

The quickest way to tell if this is the case is to look at the temperature of the return air entering the air handler. Ductwork issues might be indicated by a very cold return air temperature.

3. Auxiliary Heater Controls That Have Failed - A Qualified Technician Is Recommended

To energize the auxiliary heaters, all air handlers have some form of control. To cycle the heaters, most contemporary air handlers use an electronic control board. The heaters in older air handlers are powered by mechanical heat sequencers. Control boards and sequencers are notorious for failing over time.

4. A Qualified Technician is Recommended for a Bad Thermostat

A malfunctioning thermostat is a less likely, but potential, cause of “no heat” on a heat pump system. Even if the thermostat display says that “Aux Heat” is turned on, we’ve encountered cases when the relay outputs fail to energize the auxiliary heaters on modern electronic thermostats.

Axillary heat

5. Failure of a Heat Pump - A Qualified Technician is Recommended

A failure of the heat pump itself is another unusual, but potential, the reason for “no heat” on a heat pump system. The fact that the auxiliary heaters should energize to keep the space warm even if the heat pump stops working makes this an improbable explanation.

Some York units have a mechanism that turns off the electric heaters when the outside temperature reaches a specified level (usually around 35-40 deg). A heat pump failure may result in “no heat” if the outside air temperature is above this point.

Scenario 2: There isn’t any air coming out of the registers.


1. Incorrectly set thermostat

Thermostats that are not set appropriately cause many “no heat” calls, especially early in the heating season. Ascertain that the system is set to “Heat” or “Auto” and that the desired temperature is set higher than the space temperature.

2. Power Outage at the Air Handler

Many air handlers have multiple power breaker circuits. One breaker powers the blower and one heater on an air handler with 15kw heaters, while another breaker powers the remaining two heaters. Check the breaker panel as well as the air handler for any tripped circuits.

Thermostat Issues

A malfunctioning thermostat is a less likely, but potential, cause of “no heat” on a heat pump system. The thermostat may fail to turn on the heaters.

  • Turn the thermostat to “Off” and then back to “Heat” or “Auto” to see if that helps.

  • If you have an electronic thermostat, you should replace the batteries as well.

  • A Qualified Technician is Recommended for a Failed Blower

The heat pump and auxiliary heaters will still try to operate if the blower motor or the blower motor control fails to start. A burning or hot odor from the supply registers is usually present with this problem.

In this case, the thermostat should be set to “Off” and a competent technician should be contacted to diagnose the problem.


On a cold day, there are a few things more frustrating than turning on your heater. On a cold day, there are few things more frustrating than turning on your heating system and discovering that it only blasts cold air. The blower in some models starts up right away.

Axillary heat

As a result, cold air comes out of the vents before the furnace can fully heat them. If the air in your home never heats up, it’s a sign that something is wrong with your heating system. While many heating system repairs require the assistance of a trained professional, you can try a few troubleshooting techniques to see if you can get your heat back.

1. Thermostat Controls

Check the temperature on your thermostat. Multiple settings are available on today’s programmable thermostats. Verify that the system is set to heat and that the temperature is set correctly. An older thermostat may be still set to air conditioning.

Allow the system to reset for a few minutes. A time delay is integrated into many units. The thermostat may need to be recalibrated or replaced if all of the settings are proper.

2. Furnace (gas)

There could be several other reasons why your gas furnace isn’t working. Look for a tripped circuit breaker in your electrical panel. If the electronic starter is not powered, the burner will not light. As a result, the heater produces cold air.

Check sure the pilot light is turned on on older models. Make sure the valve on your gas supply line is open. It could have been shuttered for safety reasons over the summer.

Axillary heat

3. Furnace using electricity

The use of electric heaters necessitates the use of electricity. Check to see if the circuit breaker for the system hasn’t tripped. If that’s the case, the breaker should be reset. A breaker that keeps tripping is a sign of a short circuit or another problem. The system will give chilly air if your heating elements are burned out.

They may overheat if there is a short circuit. To prevent damage, a safety switch will cut off the heating element. Circuit breakers and heating components that aren’t working properly should be repaired by a specialist.

4. Heat Pumps are a type of heating system that uses electricity

Heat pumps, by design, produce colder air than gas and electric furnaces. If the outside temperature is really cold, they also employ supplemental heat strips. The heat pump will give cold air if these strips fail.

The system, just like in the summer, requires the right amount of refrigerant. The heat pump will not be able to transmit heat efficiently if the level is low. The heat strips and refrigerant level should be checked by an expert.


A malfunctioning thermostat is a less likely, but potential cause of “no heat” on a heat pump system. Some York units have a mechanism that turns off the electric heaters when the outside temperature reaches a specified level (usually around 35-40 deg).

If the air in your home never heats up, it’s a sign that something is wrong with your heating system.

Frequently Asked Questions

People usually ask following questions regarding heating system.

1. When is it OK to use supplemental heat?

Auxiliary heating goes in when the temperature inside your home drops two or three degrees below the temperature set on the thermostat to help warm your home faster.

2. In the winter, what temperature should I set my heat pump to?

Temperatures for Heat Pumps in the Winter

During the fall and winter months**, 68°F is the sweet spot that balances comfort and energy efficiency**, according to the Department of Energy. When your home is occupied and family members are awake, a 68°F heat pump setting keeps the living spaces comfortable.

3. When is it appropriate to utilize more heat?

When the temperature inside your home drops two or three degrees below the temperature set on the thermostat, auxiliary heating kicks in to help warm your home faster.

4. Why aren’t heat pumps utilized in the north?

Heat pumps have a reputation for not working properly in colder climates throughout the winter. They’re more efficient in locations where temperatures don’t drop below freezing because of the way they’re made.

5. Is 72 degrees Fahrenheit a reasonable temperature for heating in the winter?

Set your thermostat anywhere between 72° F and 66° F depending on the time of day and whether or not your home is occupied. According to the majority of HVAC professionals, this is the case.

6. When a heat pump reaches a certain temperature, it stops working?/

When temperatures dip to between 25 and 40 degrees Fahrenheit, heat pumps lose efficiency. When the temperature is over 40 degrees, a heat pump works well. Heat pumps lose efficiency when the outside temperature drops below 40 degrees, and they use more energy to conduct their functions.

7. Why do old people constantly seem to be cold?

Seniors’ bodies may be unable to create enough heat to maintain a “normal” temperature of 98.6 degrees as they age due to a natural decline in metabolic rate. Slower circulation makes it more difficult to keep heat in the body. This may be due to aging or drug adverse effects.

8. Inside a house, how chilly is too cold?

In the winter, the World Health Organization (WHO) recommends keeping your thermostat at 64 degrees Fahrenheit (F) while you are at home. If there are infants or elderly people around, the temperature should be kept below 70 degrees.

9. what type of vitamin deficit causes you to feel cold?

Anemia can be caused by a lack of vitamin B12 or iron deficiency, which can make you feel cold. Chicken, eggs, and fish are good sources of B12, and patients with iron deficiency should eat poultry, pork, fish, peas, soybeans, chickpeas, and dark green leafy vegetables.

10. Is it true that heat pumps consume a lot of electricity?

Heat pumps use some electricity to operate, but only a little amount. Modern heat pump systems can transmit three to four times more thermal energy in the form of heat than they require in electrical energy to conduct this function - which the homeowner is responsible for paying for.

11. Will a heat pump function in a 0°F environment?

Modern heat pumps may function effectively in sub-zero temperatures for a short length of time. A gas furnace or a dual fuel heat pump system with a gas-powered backup heat source is the ideal option if you live in a cold-weather climate with extended periods of subzero temperatures.

12. Is it possible to leave a house unheated during the winter?

Almost any room in the house can be closed off or have the temperature significantly adjusted for the winter. However, not every room can be left completely unheated because the flooring would fracture, any plaster cracks will spread, and ice will develop within the windows, ruining the finish.

13. Is it more cost-effective to set your thermostat to a single temperature?

However, it turns out that the only true benefit of maintaining your thermostat in one setting is convenience. Sure, the steady temperature is convenient whether you’re on vacation or away for the weekend, but there are no added benefits when you’re at home.

14. How do snowbirds prepare their homes for the winter?

External doors and windows should be secured with deadbolt locks and security-type hinges. Slide locks or other similar security locks should be installed on sliding glass doors.

Keep any valuables you won’t be bringing with you in a safe place. Keep valuables in a safe deposit box or another secure offsite location if you’re not taking them with you.

15. Why do empty rooms feel so cold?

Empty rooms are always colder.

It may appear strange, yet it is a straightforward climate principle. Air heats and cools more quickly than objects, yet it does not keep its temperature. Furniture, drapes, clothes, and decorations absorb heat and then re-radiate it, making the air warmer.

16. How to Prepare Your Home for a Winter Vacation When You’re Alone?

Turn the water supply off. The most crucial thing you should do is turn off your water supply, especially if you’ll be gone for the whole winter.

  • Drain the waterlines.

  • Pipes should be insulated.

  • Reduce the temperature.

  • Unplug all of your appliances.

  • Remove the garbage.

17. What do snowbirds do with their homes when they leave?

Some snowbirds rent out their homes. When they return north, some snowbirds rent out their vacation homes. Snowbirds live in their summer homes between April and October, and some put their winter homes on the market for rent.


A heat pump’s auxiliary heating system is referred to as auxiliary heat on your thermostat. Auxiliary heat is activated when the temperature inside your home falls below-set levels. Most of the time, supplemental heat is activated because the home’s temperature is set too high.

The emergency setting must be turned on manually and should only be used when the temperature is below 30 degrees. A malfunctioning thermostat is a less likely, but potential cause of “no heat” on a heat pump system.

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What is auxiliary heat. Auxiliary heat is a heat pump thermostat set. If a heat pump is having a challenging period coming up to a particular temperature fast due to excessively chilly outdoor temperatures, the “aux heat” arrow indicates that a secondary heat basis (commonly gas or electric) has been deployed.

The distinction Between Auxiliary & Emergency Heat:

In Florida, you have got three forms of heating sources along with your HVAC system: For this discussion, we are going to specialize in the distinction between a conventional heater/furnace and an apparatus system. Several Floridians WHO lived up North don’t perceive the difference between auxiliary heat and emergency heat.

What’s the Difference?

Auxiliary heat is mechanically activated once there’s not enough doors heat. During this mode, the warmth pump continues extracting the maximum energy as doable. However, it conjointly adds heat from a secondary supply to form the distinction.

This secondary heat supply is often electrical heating coils integrated into the system. As out of doors temperatures rise, and secondary heat isn’t any longer needed, the unit mechanically turns off the auxiliary electrical coils.

Emergency heat may be a mode the user manually selects if the unit isn’t providing heat for a few reasons, like a malfunction. Emergency heat activates the secondary heat supply to supply 100% of needed heat. The system continues to control in emergency mode till the user manually turns it off.


AN example once emergency heat could also be used can be once a section has been ordered for a required repair and your HVAC skilled has shared that by changing to emergency heat, your home can still heat for your family.

What area unit Auxiliary Heat & Emergency Heat?

Auxiliary Heat – this can be the secondary heat supply that activates mechanically.

Emergency Heat – this can be after you activate the secondary heat supply.
The distinction between auxiliary heat and emergency heat is just the name. Each heat area unit has the same heat components; however, the area unit is labeled otherwise.

Auxiliary Heat:

Here in Everglade State, we usually use the warmth pump for our primary supply of warmth once heating the home; but, this unit conjointly contains a limit. An apparatus will satisfy your home’s heating wants as long as the out of doors temperature remains at or higher than forty-five degrees.

At temperatures around forty-five degrees, the skin coil will and can freeze up, which can cause the system to travel into de-ice mode. Whereas in de-ice manner, the out of doors unit can signal the air handler to show on the auxiliary heater.

This heater is an electrical heater like a kitchen appliance and can offer supplemental heat to the house, whereas the outside door unit defrosts itself.


Once the release of the doors system is defrosted, the auxiliary heater turns off, and the system continues in apparatus mode.

Emergency Heat:

  1. Emergency heat may be a term we tend to use for once the house owner should force the system into the electrical heating mode if their apparatus system has been unsuccessful or isn’t operating correctly.

  2. This heater is the same because the auxiliary part is solely employed in a distinct format.

The heater is often not designed to heat your home to eighty degrees, however solely as a supplement heat supply. In contrast, the warmth pump is in de-icing mode or as AN emergency backup in a system failure.

Auxiliary Heat’s Functions:

The first performance is to copy the warmth pump if the thermostat contains a distinction of three degrees or a lot of from the set temperature to the particular temperature within the house. If this happens, the warmth pump and strips can run along to form hotter air to heat the home efficiently. Once the thermostat point is among two degrees of the temperature within the house, the auxiliary heat can be put off.

The second performance is once the out of doors system goes into de-ice mode, as declared higher.

When we kick off to try and do our 77-point listing on your system, we’ll kick it into de-ice mode to form positive it’s operating. We essentially freeze the system up and create the instrumentation work a touch more durable to form positive you’ll have heat after you want it.

Which is Better?

If out of doors temperatures briefly drop and your apparatus will not extract enough heat, the correct mode is automatic auxiliary heat. During this mode, the warmth pump still contributes the maximum amount of heat, minimizing demand from electrical heating coils. In emergency mode, conversely, the warmth pump performance is entirely disabled, and also the system depends entirely on secondary heating coils.

As a result of electrical heating, waves consume scores of electricity, heating prices within the emergency mode can increase dramatically if systematically used for long periods of your time.

Why you must ne’er Use Emergency Heat (unless you have entirely to):

Before you bit that Emergency Heat setting on your thermostat, scan this! The Emergency Heat or Auxiliary Heat setting is the second stage of your heating plant used once the temperature is too low for the warmth pump to take away heat from outside, usually below thirty-five degrees Fahrenheit.

Your heating plant will then use the alternate supply to supplement the warmth. However, if you force the system into the Emergency Heat mode, it becomes the only energy supply instead of its supposed performance.

Switching your Thermostat to Emergency Heat will Lead to:

High energy bills:

The cost of running your home on Emergency Heat would be astronomical. Turning to the current setting switches your heat supply from the warmth pump to the electric heat strip, which is considerably less economical and a lot pricey.

Taxing your system:

Turning on emergency heat forces your system to bypass the warmth pump altogether and work like most heat supply isn’t engaging at all. This puts an excellent strain on the backup part that’s solely meant to be employed in extreme circumstances for brief periods of your time.

When operating correctly, your heating plant can utilize your Emergency Heat once the first system cannot handle dominant temperature on its own or there’s a haul along with your heating plant. If your fan doesn’t activate either, set your thermostat; therefore, the system doesn’t be. While not air movement, emergency heat will cause injury to your out of doors unit. You must ne’er activate the Emergency Heat manually unless your apparatus has been unsuccessful entirely.

If that’s the case, you must have your heating unit examined and repaired like a shot. If you want to activate the Emergency Heat, don’t hesitate to get in touch with Wentzel’s and permit the North American nation to handle the underlying issue.


Remember, don’t switch to Emergency Heat simply because it’s cold; solely do this if your apparatus isn’t any longer heating your home the least bit.

Auxiliary heat is required when:

The temperature outside is below freezing.

Heat pumps have one drawback:

They lose potency because the temperature drops.

Heat pumps area unit extremely economical to concerning 32°F. Below phase transition, your apparatus merely can’t draw enough heat from the cold air outside and can kick on its auxiliary heat mode to come up with heat for your home.

So, before your decision is an expert to diagnose a haul, check the out of doors temperature. If it’s a strangely cold day in San Marcos, don’t be shocked to examine “AUX heat” on the thermostat.

Your thermostat is looking for a hot temperature increase:

When the temperature within your house is over 2–4°F higher than your thermostat’s set temperature, the auxiliary heat can activate. (The actual temperature differential can rely on your apparatus model.)

This happens as a result of your system is attempting to come up with a great deal {of heat|of heatth} to warm your home faster than it might with traditional apparatus heating. Once the within temperature reaches the set thermostat temperature, your system should return to victimization conventional apparatus heating.


To avoid this downside, we tend to advocate limiting; however, typically, you raise the temperature over 2–4°F.

The heat pump is in de-ice mode:

Although we tend to don’t get a great deal of sub-freezing temperatures in San Marcos, your apparatus may enter what’s referred to as “defrost mode,” which prevents your out of doors unit from phase transition over.

In de-ice mode, your system can run in cooling mode for a couple of minutes to permit the coils within the outside doors unit to heat up.

You’ll recognize your system is in de-ice mode if the out of doors fan has stopped current and you see puffs of steam returning from the unit. Some models even have a blinking lightweight on the out of doors unit that indicates your unit is in de-ice mode.


During de-ice mode, your system can use auxiliary heating to heat your place in the meantime. The warmth pump ought to sit back to traditional heating mode once a couple of minutes.

How To Fix Ecobee Auxiliary Heat Running Too Long?

All the users WHO have recently put in AN Ecobee thermostat in their good house have received a weird message stating, “Auxiliary heat running too long.” This has raised concern among them on what precisely this message will mean and what they’ll do to mend it.

If you’re conjointly one amongst these users, you have nothing to stress concerning. Today, we will be taking a glance at ways that on however you’ll be able to fix Auxiliary heat running too long a message on Ecobee.

1. Change Your Aux Heat Threshold:

Extra kicks in whenever the warmth pump cannot heat a chilly area properly. It acts as a secondary heat supply and helps you warmth your site quickly. However, several users counsel keeping the employment of auxiliary heat as low as doable.

In this case, the trick would be to be told precisely however low your apparatus will run properly. Once you discover that out, merely modify the auxiliary heat threshold around that temperature. You’ll notice the edge settings by getting to Settings > Installation Settings. This may drastically lower the employment of extra heat that ought to be ideal for you.

2: Configure Your Installation Settings:

Same because you will wish to envision different installation settings on the device in the beginning. Make sure the edge isn’t set to too high or too low. You’ll be able to conjointly set it to confirm once it ought to use the auxiliary heat mechanically.

There area unit lots of different settings and modes likewise that you would possibly wish to envision. Suppose you continue to have the manual, attempt giving it a scan.


Aux heat has multiple settings that will get to be organized. Make sure that your Aux runtime is about to the correct quantity likewise.

Frequently Asked Questions:

Here we discuss some frequently asked questions:

Q1: Ought to shut down my apparatus at night?

A: It would help if you didn’t have to be compelled to shut your apparatus off at midnight. Heat pumps are designed to figure at most potency once set to the specified temperature and allowed to run as required. Heat pumps are designed to control the home’s temperature as directed by the thermostat.

Q2: However, do I know if my apparatus is functioning correctly?

A: The most thanks to telling if your system is functioning as meant is to hear the unit running efficiently**. You’ll be able to listen to the system once it activates,** once the fans begin to figure and stop, and once air passes through the ducts. Aside from that, the unit itself ought to dummy up, with no inarticulate or creaking sounds.

Q3: What causes an apparatus not to heat?

A: Low refrigerant charge – If your system is low on refrigerant charge, it will not be ready to carry on with either heating or cooling demand. Another sign of a typical refrigerant charge could be a frozen coil. Dangerous reversing valve – If you’ve got an apparatus not heating, however, it works in cooling mode. You may have a stormy reversing valve.

Q4: However, can I tell if my apparatus has auxiliary heat?

A: Watch your thermostat. Aux heat seems like a setting on a wall thermostat. If you do not see associate degree aux heat facultative switch or associate degree aux heat lightweight on your thermostat, then your heating plant does not have it. On the mechanical or instrumentation facet, heat pumps with aux heat contain another section to their air handler.

Q5: Why would my thermostat say auxiliary heat?

A: Once you see the “aux” heat indicator on your thermostat, it means that your apparatus required some facilitate reaching the specified temperature. It activates mechanically once the temperature falls 2 degrees below the specified setting and turns off mechanically once the target temperature is reached.

Q6: What temperature ought to I set my apparatus in the winter?

A: Ideal Winter apparatus Temperature Settings.
According to the Department of Energy, 68°F is the sweet spot that balances comfort and energy potency throughout the autumn and winter months. Once your house is occupied, and family members are awake, an apparatus setting of 68°F keeps the living areas relatively hot.

Q7: How long ought an apparatus run per day?

A: It’s traditional for your device to change on and off , betting on the temperature within the house. A decent rule of thumb is that it ought to endure about ten to fifteen minutes before motility down once more. Typically, if the device is turned on and off, it may indicate a retardant.

Q8: What will a replacement apparatus system cost?

A: Average cost: $3,875 - $10,000.
A new apparatus will value between $3,875 to $7,625, betting on the dimensions of your home, economical energy ratings, brand name, and also the sort of apparatus you put in. A mini-split passageway apparatus with four multi-zone indoor air handler units may value up to $10,000 to put in.

Q9: However, typically, will an apparatus ordinarily defrost?

A: Roughly every thirty-five minutes.
Generally, heat pumps can often melt once frost conditions occur. However, defrosting frequency ought to be not quite roughly thirty-five minutes. The length of your time the warmth pump can melt can vary. However, usually, it mustn’t take longer than ten minutes.

Q10: At what temperature will an apparatus switch to emergency heat?

A: The Emergency Heat or Auxiliary Heat setting is that the second stage of your heating plant that’s used once the temperature is just too low for the warmth pump to be ready to take away heat from outside, generally below thirty-five degrees physicist.


Aux heat ought to solely kick on once {the heat|the heatth} pump cannot manufacture sufficiently heat to warm your house on its own. This can usually be caused by one of three factors. Once it’s below 35° outside, you are attempting to heat your home by 3° or a lot of, or your apparatus is in de-ice mode.


What is auxiliary heat. Auxiliary heat on your thermostat refers to your backup heating inside your setup, otherwise called resistance heating. This usually takes place once the indoor temperature on your thermostat reaches 2-3 degrees colder than the set indoor climate temperature.

What Will Auxiliary Heat Mean:

First, let’s address the most concern that we typically hear once somebody wonders what auxiliary heat will mean. Is AUX heat bad? The short answer isn’t any. Aux heat could be an essential mechanism that keeps your setup properly running once the outside temperature drops. Since this unit doesn’t work identical to a chamber, it will get cold.

Consequently, you would like a backup technique involving heat strips in your unit. Once the outside temperature dips very low, your chilly team can’t produce enough heated air to fritter into your home. Therefore, heat strips (basically electrical coils) activate, providing a lift to heat your home.

Additionally, aux heat prevents your setup from cooling. Moreover, as wetness build-up in your unit turns into ice, the warmth pump switches to dissolve mode. During this case, heat air flows from your home back to your team, melting the ice.

However, since these heat strips use vast amounts of electricity, you don’t wish them running all the time. So, next, consider ought to auxiliary heat comes back on? Once your vents finally get the kick they have to heat up, the warmth strips ought to shut down. Likewise, once the ice melts on your unit, auxiliary heat ought to stop.


If it keeps running, decide on a heating repair company as quickly as possible to avoid a massive invoice.

Will Auxiliary Heat Mean And May It’s Running Often?

Our cooling weather brings a standard question: What will auxiliary heat mean, and is it unhealthy that it’s running? Typically, there square measure a couple of answers. Therefore, recognizing that one most closely fits your scenario and understanding however your setup works is valuable. Plus, obtaining a grasp on aux heat generally clarifies the method.

What Is Auxiliary Heat And Why You Ought To Worry Once It Stays On:

As we’re nearing the coldest time of the year, it’s crucial to ensure that your heating is functioning correctly. If it’s not, now’s the time to act before the night-time weather systematically stays below cooling. Sometimes, you’re unaware of a heating malfunction. For instance, one of the foremost common heating problems is heaters staying on auxiliary heat.

First, this is often difficult if the low temperature is unremarkably below 32° F. However, you’ve got a drag if the weather gets hotter and your auxiliary heat stays on. Once that happens, it’s time to decide the skilled technicians to draw a bead on Heating & Cooling. Stop curious about what’s auxiliary heat and find the matter mounted currently.

What Is Auxiliary Heat And What Will It Mean For Your Heater?

Has your heating been stuck on aux heat? Maybe your heating isn’t operating as effectively as it ought to be? Finally, has your heating bill been atrociously high over the past month? Due to our draw a bead on specialists, you oughtn’t to marvel what’s auxiliary heat and the way to mend it. Hence, if you have an associate degree aux heat issue, allow us to look out for it for you.

Before you decide on our heating specialists, we would like you to apprehend what auxiliary heat is initially. As you recognize, your setup works laborious to heat your house. In contrast to a chamber, a design doesn’t produce its heat however takes heat from the skin air. The matter happens once the temperature drops below cooling at 32° F, as there isn’t enough heat within the atmosphere.

Once that happens, your system switches to emergency heat, otherwise called auxiliary heat. Besides a coffee temperature, your setup conjointly goes onto emergency heat if there’s ice frozen on its surface.


Ice will happen if there’s a drag with heat strips that work to keep the skin defrosted. In addition, generally, your system has low refrigerant levels or drag with the outside motor fans.

When does one Not wish Auxiliary Heat On?

Auxiliary heat uses resistance heating to heat your home. Since resistance heating is far less economical than your setup, you merely wish it to get on once necessary. Otherwise, your auxiliary heat is functioning once it shouldn’t be and driving up the price of your heating bill.

To recap, auxiliary or emergency heat ought to solely get on once the skin temperature is below cooling. Down here within the south, that ought to essentially happen in the dark and through the occasional violent storm. However, if the weather is hotter and higher than the cooling level, your auxiliary heat ought to mechanically shut down.


If it doesn’t, then you’ve got a drag. So, don’t wait and run the chance of a whole system breakdown or a high heating bill. If your heating is stuck on aux heat, decision draw a bead on nowadays.

Besides System Repairs, draw a bead on conjointly will Installation and Regular Maintenance:

In addition to heating repair, draw a bead on conjointly will heating installation and regular maintenance. Thus, if your heating decides to bite the mud, allow us to install new heating for you professionally. Lastly, the most straightforward thanks to stopping a system failure is regular maintenance.

This service permits the US to check your system and its instrumentation often to ensure that everything is functioning expeditiously. Therefore, stop the breakdowns before they happen with our quick and friendly routine maintenance. To be told additional concerning any of our services or care plans.

Emergency & Auxiliary Heat: What’s the difference?

Emergency Heat:

The Emergency Heat activates a setup that confuses plenty of individuals. What’s it? Once do I exploit it? Do I flip it on once it’s freezing? Of these square measure friendly questions! Heat pumps want a supplemental heating supply. Mainly once the weather is below forty degrees, these additional heating sources square measure things like the electrical resistance heating at the indoor unit, gas, oil, or perhaps hot-water backup systems.

Other heating sources are called “second-stage” or “backup” heating. Your setup solely is that the “first stage” heating. Emergency Heat is once you use your “second-stage” (supplemental heat) by itself while not mistreatment your “first stage” (heat pump)

So once must you use your Emergency Heat? Precisely because the name implies, in emergency things solely. It’s used once there’s one thing wrong along with your “first stage” heat. For instance, if your home is not heated and it’s due to one thing that went on to your outside unit, then it’s time to show Emergency Heat on and demand service.

Once you activate Emergency heat, this may solely activate the indoor unit and backup heat. Would you please decide to urge service once this happens? Having Emergency Heat on will and can be costlier to run. This is often why it’s solely employed in associate degree emergency scenarios.


Note that if your Emergency Heat lightweight is on, your thermostat isn’t set to Emergency Heat. This is often an associate degree indicator. There’s a drag along with your setup, and you ought to demand recommendation and repair.

Auxiliary Heat:

Auxiliary Heat can activate mechanically once heat does not expeditiously transfer heat from the skin air to set up. This is often once the skin is around 35-40 degrees and also the indoor temperature is about 3 degrees cooler than the thermostat setting. The thermostat can sense this and mechanically switch on electrical heat strips, lightweight turning on the “AUX” heat. This may give extra warmth to PRN.

It will be got to be noted if your thermostat stays in “Aux Heat” even once temperatures outside rising, you ought to decide to own it repaired. Auxiliary heat uses resistance heating, far less economical than your setup. Therefore, heating stuck in AUX heat can run up an associate degree energy bill. If you’ve got a design, it’s best to extend your heat setting by solely 2 degrees at a time to stop your auxiliary heat from in operation.

Frequently Asked Questions:

Here we discuss some frequently asked questions:

Q1: Is it unhealthy if auxiliary heat comes on?

A: Is AUX heat bad? The short answer isn’t any. Aux heat could be an essential mechanism that keeps your setup properly running once the outside temperature drops. Since this unit is not identified as a chamber, it will get cold.

Q2: Is auxiliary heat additional expensive?

A: Auxiliary heat will handle different extreme temperatures using electrical heat strips. Sadly, this suggests that it’s costlier than the standard heat. Whereas a furnace isn’t as economical as a setup, it’s additional economical than a setup mistreatment auxiliary heat.

Q3: However, do I stop my auxiliary heat from coming back on?

A: Shut the door and shut the vents so that the remainder of warm and cozy air will be redirected to the rest of your home. If the temperatures square measure very frigid outside, even this might be excessive for your unit. You will get to build additional changes to your home to keep the auxiliary heat from approaching.

Q4: What’s the distinction between heat and auxiliary heat?

A: Setup systems have two units - one outside and one within the house. The unit outside your home is a setup, also, the unit within the place is that the auxiliary heating. The emergency heat setting should be manually switched on and may solely be employed in temperatures below thirty degrees.

Q5: However, typically ought to auxiliary heat comes back on?

A: Once outside, temperatures drop below forty degrees. Whereas undergoing the dissolve cycle. Once there’s a three-degree distinction or additional within the current temperature in your home and the thermostat setting.

Q6: What causes auxiliary heat to return on?

A: Auxiliary heat can kick on once your setup cannot deliver enough heat to heat your home. Typically, your design can energize the auxiliary heat strip within your secondary heating supply to assist reach its set temperature quicker.

Q7: Will auxiliary heat use additional electricity?

A: Auxiliary heat uses resistance heating, far less economical than your setup. Therefore, heating stuck in Auxiliary heat can run up the associate degree energy bill. If you’ve got a design, it’s best to extend your heat setting by solely 2 degrees at a time to stop your auxiliary heat from in operation.

Q8: Why is my auxiliary heat processing cold air?

A: Heat Pumps.
They conjointly use auxiliary heat strips if the skin temperature is freezing. If these strips malfunction, the warmth pump can fritter cold air. The warmth pump cannot transfer heat expeditiously if the extent is low. Knowledgeable ought to check the warmth strips and refrigerant level.

Q9: What will auxiliary heat mean, Honeywell?

A: Auxiliary Heat or Auxiliary heat is the backup heat that activates the mechanical device for the initial stage to maintain your temperature setting. Once the thermostat is during this position, the robotic device doesn’t run, solely the Emergency heat runs.

Q10: However long are you able to run auxiliary heat?

A: If you’re employing a rather dear Aux heat system. By default, this point is ready for 5 minutes. This means, if your aux heat is termed upon and canceled straight off, it’ll still endure 5 minutes before moving down.

Q11: Ought to I run auxiliary heat on?

A: Primarily, auxiliary heat uses ohmic resistance heating to heat your home. Since ohmic resistance heating is way less than your apparatus, you merely wish it to get on once necessary. To recap, auxiliary or emergency heat ought to solely get on once the skin temperature is below state change.


Heat pump systems have two units - one outside the residence and one inside the house. Auxiliary heating turns on automatically to assist heat your home faster if the temperature drops unexpectedly. The emergency heat setting must be manually exchanged and only used in temperatures below 30 degrees.