What does EM heat mean? Look at the thermostat that controls your home’s heating and cooling systems. If you see a switch or button labeled “EM heat,” your home probably has a heat pump. The first part of the phrase “EM heat” means emergency heat. The pump emergency heat setting on your thermostat controls your heating system’s auxiliary heat source, which kicks in when outside temperatures drop below a certain threshold, usually something colder than 35 to 40 degrees Fahrenheit. Now that you know the answer to the original question—What does EM heat mean on a thermostat?—let’s dig a little deeper into the meaning of this setting.

The heat pump of your heating system pushes warm air from inside your home to the outside during hot weather and moves heat toward the inside during cold weather. During cold weather, however, a heat pump may not be able to draw enough heat into the home to provide the desired level of heating. The system’s emergency heat source can then be activated. An auxiliary source might be connected to the home’s gas furnace or might be in the form of electric radiant heat strips. Low outdoor temperatures make it harder for your heat pump to heat your home on its own, so EM heat helps make up the difference.

What does EM Heat Mean?

EM heat should automatically kick in during the heat pump’s cycle phases when it switches off temporarily to defrost the outside unit. It is normal for the coils in the outdoor unit to collect moisture from the air in colder weather, which turns into frost on the coils. During this phase, the EM heat in the system switches on to warm the house for a short time before the heat pump kicks in again.

The most important thing to remember about the EM heat setting is that it is only intended to be used in extremely limited circumstances. The EM heat setting is significantly more expensive than the regular setting. As a result, while EM heat can be activated manually in some systems, homeowners are advised not to do so unless the heat pump has failed and a heating and cooling professional has consulted.

EM heat is not a feature homeowners use often, so they have any questions about it. We will cover some of the most common questions and problems that homeowners have regarding emergency heat, such as when they should use it, how to fix it if it breaks, and what to do if it runs constantly.

A common question about this setting is the difference between aux heat and emergency heat.

Aux Heat Vs Emergency Heat: Are They the Same?

The question of aux heat vs emergency heat has been asked by many people: Are they the same thing, or do they differ? If we compare aux heat vs emergency heat, they both refer to the same thing, and they are somewhat interchangeable.

Homes with heat pumps have a two-part system: The heat pump, which is the outdoor element, and the auxiliary heating source, which is the indoor element. The auxiliary source can either be a gas furnace or a series of electrical radiant heat strips. EM heat, or emergency heat, is a setting on your thermostat that indicates when this auxiliary system is being used, and it can also be switched on manually if your heat pump malfunctions or stops working.

If your home’s auxiliary heat source is on, the thermostat will indicate that EM heat is on. Alternatively, you can temporarily turn on the EM heat to heat your home if your heat pump is not working. Either way, you need to know under what conditions EM heat should be activated.

Emergency Heat: When To Use It

Most homeowners don’t know exactly when to turn on emergency heat, while others think it’s just for extra-cold days to keep their homes warm. However, EM heat should only be used when the heat pump isn’t working. You should also call a licensed heating specialist to service the heating system as soon as possible. The emergency heat setting is intended to be used only temporarily to keep the house warm while the heat pump is off-whether it is actually malfunctioning and needs to be repaired or merely defrosting and is due to restart soon.

When the EM heat setting on a homeowner’s thermostat is manually switched on, the heat pump is bypassed, forcing the system’s auxiliary heat source, such as the furnace or radiant heat strips, to kick in and provide all of the home’s heating. Due to the fact that EM heat uses far more energy than a properly functioning heat pump-based system, long-term use of the EM heat setting would be quite expensive and should be avoided. This could explain why your electric bill is so high if you have been using aux heat vs EM heat for most of the month. You’ll want to know what to do if you find yourself in this situation.

EM Heat Not Working: What Should I Do?

EM heat not working? It’s easy to assume your EM heat isn’t working when you feel cold air coming out of your vents. Even, when the heat is on. But that’s not always the case. It is entirely possible that when it is extremely cold outside. Such as in the twenties or below, your heating system’s heat pump and emergency heat source. Both are functioning normally but simply aren’t able to heat the home properly.

EM heat is not working or isn’t working efficiently for several reasons, including the possibility that your heating unit is low on refrigerant. Another possibility is that a tree branch broke off due to ice and fell onto your outdoor unit, causing damage. Your outdoor unit’s coils may have frozen as a third possibility. If your home’s emergency heat source is not working properly and cannot warm up your outdoor unit. So it works as intended.  You will need to have the system inspected by a licensed heating specialist. Who can accurately diagnose the issue and repair or replace any malfunctioning parts.

What Should I Do If My Heat Pump Runs Constantly During Cold Weather?

You are not the only one concerned that your home’s heat pump constantly runs during cold weather. It is normal for a heat pump to run constantly in winter-at least when temperatures are consistently below 30 degrees. If the EM heat vs aux heat or both indicator on your heating system is also turning on periodically. It means the auxiliary heat source in your home is also doing its job. Just by turning on temporarily when the heat pump is in defrost mode.

If your heat pump constantly runs in its cooling mode during the summer, that might indicate a problem. It’s good to make sure the heater’s air filter is clean. The thermostat is set correctly, the condensate pump is plugged in, and the outdoor unit is running.

The refrigerant levels in your heat pump unit could be too low if you have performed all of these checks. Which would indicate a leak in the system. In addition, it is possible that the solenoid valve is malfunctioning or has failed. Resulting in the system getting stuck in AC mode. A third possibility is that the unit is too small for the size of your home. So it can’t effectively cool the entire room. In this case, it’s time to call a technician to determine why the system stopped working properly.

The best people to handle problems with your home’s heat pump or emergency heat setting are heating specialists. If you have a heating question or concern. A licensed HVAC professional should be consulted. As these technicians have the experience and expertise necessary to provide an accurate diagnosis. They determine the best way to fix your home’s heating system.

Your heating problems can be handled by a professional HVAC technician.

A malfunctioning heat pump can make your home uncomfortable when temperatures drop drastically. On the other hand, if the emergency heat is constantly running. You may run into another issue if you end up with a high electric bill. No matter what the problem is with your heating system. Licensed HVAC technicians can get your space back to normal quickly.

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