What Is Emergency Heat on HVAC Thermostats?

Do you have any questions regarding the usage of your HAVC system? Call Fast Air Repair for all the answers.

If you have a heat pump, you’ve most certainly seen a setting on your thermostat labeled “EM heat,” which stands for emergency heat. Many people mistake this setting for another gear or two they can go to when they need extra warmth, but that’s not the reality.

What is emergency heat on HVAC thermostats? When is the right time to use the setting? Fast Air Repair, the top choice for heating and cooling services in Ocala, FL, covers the details in this post. 

Understanding Emergency Heating in HVAC Systems

Emergency heating, or “EM heat,” refers to a special setting that should control your home’s backup heating system. Homes that have a heat pump in colder climates often need to rely on this backup heating system.

Such homes also have a secondary heat source, which typically includes an electric heating strip or a gas furnace. The secondary heat source kicks in when the outside temperatures drop below 35° Fahrenheit.

At this temperature, the average air source heat pump will no longer pull heat from the outside air. Some of the components may also start to freeze. The emergency heating system will work for as long as the temperatures stay low to keep your indoor space from freezing over.

Keep in mind that the emergency heating function may not switch on and off automatically. It all depends on your thermostat’s design and the configuration of your HVAC system.

In many cases, the emergency heating setting can trigger your backup heating automatically when the temperatures dip too low. However, you’ll need to turn off the setting manually. However, some setups require switching to and from emergency heating manually.

Emergency Heat vs. Auxiliary Heat

What is emergency heat on HVAC thermostats? Isn’t it the same as auxiliary heat?

Looking at how emergency heat works in heating systems, you may get confused about how it differs from the auxiliary heat setting, which also exists in some thermostats. However, these settings have significant differences.

As we’ve established above, emergency heat is a setting that triggers a separate heat source not connected to your heat pump. However, auxiliary heating only triggers a special setting in your heat pump when it identifies a two- or three-degree difference between your thermostat setting and the indoor temperature. 

The setting will activate supplemental heating, which will run for around two hours to balance out the temperatures. The additional heat comes from a heat strip within the heat pump. Therefore, auxiliary heating will only work if your heat pump works properly.

If your heat pump has frozen over, it won’t work. In that scenario, you’ll need to revert to the emergency heating if you need more warmth.

Benefits of Emergency Heat Setting on HVAC Systems

The main benefits of the emergency heat setting on HVAC systems include the following:

• More reliable heating. When the temperatures dip too low, the emergency heating setting kicks in to compensate for the heat pump’s inability to keep your home warm. Thus, you can relax in comfort through the winter months.
• Longer equipment lifespan. HVAC emergency heating features eliminate the need to keep trying to use your heat pump in unfavorable weather conditions. Thus, the system will last longer overall.

When Should You Use Emergency Heat in Ocala, Florida?

You should only use the emergency heat function in HVAC systems in real emergencies. For most people, this would mean a temperature drop below freezing conditions. However, Florida doesn’t experience such significant temperature dips in the winter.

Therefore, your heat pump should work normally throughout the winter months without drawing on your emergency heating. In fact, it’s not uncommon to find Florida homes without a backup or emergency heating setup.

However, if you do have it, you may need to use the emergency heat setting in the following scenarios:

Your Heat Pump Is Not Working

Floridians enjoy some of the warmest weather in the winter months, but you may still need the heat pump to deliver some warmth on a few of the coldest nights of the year. If your heat pump fails to provide the warmth you need, you can switch to emergency heating until you can call in an HVAC technician.

Your Heat Pump Is Undergoing Maintenance

Your HVAC technician will need to turn off the heat pump during maintenance or while carrying out any repairs. You can switch to emergency heating if you can’t stay comfortable by throwing on a few layers until they have completed the maintenance.

Why You Should Not Use Emergency Heating for Too Long

The whole idea of emergency heating is to give you a backup heating source. We do not recommend converting it into your main heating option.

Your heat pump offers greater energy efficiency than the main options for backup heating. Therefore, you may end up paying more to heat your home overall.

Before turning the backup heating into your primary heating, you should discuss your options with a qualified HVAC technician to ensure you are making the right choice. 

Get Expert Guidance on Your HVAC System From the Fast Air Repair Team in Ocala, Florida

HVAC systems are complex. It often feels like you learn something new every time you have to deal with the system. Also, looking at how easy it is to throw the components off balance, it’s only natural that you want to take the right precautions before making any changes to the system.

Something as simple as choosing the wrong setting on your thermostat can leave you uncomfortable through the winter or summer. So, if you find yourself asking, “What is emergency heat on HVAC thermostats?” you’re doing the right thing! We hope our post has cleared up any confusion in that regard.

If you still need any further emergency heat mode explanation or help with choosing top-rated HVAC systems, we are ready to listen!

Call Fast Air Repair in Ocala, Florida, today at (352) 329-3437 to book a consultation.