When to Use Emergency Heat on Heat Pump? Heat pumps are efficient and versatile devices that can provide heating and cooling for your home. However, they may need to work better in extremely cold weather or when they are damaged or malfunctioning. In such cases, you may need to use the emergency heat setting on your thermostat to keep your home warm and comfortable. But what is emergency heat, and when should you use it? In this blog post, we will explain emergency heat, how it works, when to use it, and how to avoid using it unnecessarily.
What Is Emergency Heat?
Emergency heat, also known as auxiliary heat or backup heat, is a secondary heating source that can supplement or replace your heat pump when it cannot provide enough heat for your home. Emergency heat is usually activated by a switch or a button on your thermostat, labeled as “EM HEAT,” “AUX HEAT,” or “BACKUP HEAT.” When you turn on the emergency heat, your heat pump will stop running, and your emergency heat source will take over.
The type of emergency heat source depends on the type of heat pump system you have. There are two main types of heat pump systems: air-source and dual-fuel.
Air-source heat pumps are a cost-effective and eco-friendly way to heat your home. They use electricity to power the heat pump and emergency heat source. Despite their high energy consumption, they remain popular for homeowners seeking a reliable and effective heating solution.
Dual-fuel heat pumps use electricity, gas, or oil to power the emergency heat source, usually a furnace located outside the air handler. Although efficient, they are expensive to install and maintain due to the separate fuel supply requirement.
How Does Emergency Heat Work?
Emergency heat bypasses the heat pump and uses the secondary heating source to heat your home. When you turn on the emergency heat, your thermostat will signal the heat pump to shut down and the emergency heat source to turn on. The emergency heat source will heat the air and distribute it to your home through the ductwork. The emergency heat will run until you manually turn it off or the thermostat reaches the desired temperature.
Emergency heat can be used in two ways: manually or automatically.
Manual emergency heat is when you turn it on yourself by pressing the switch or button on your thermostat. You may do this when your heat pump is malfunctioning or you want to warm up quickly. However, you should only use it in emergencies, such as when your heat pump is broken or frozen and you need heat until a technician can fix it. You should refrain from using it regularly, as it can waste energy and money and damage your system.
Automatic emergency heat is when it turns on by itself, without you pressing the switch or button on your thermostat. This may happen when the outside temperature is too low for your heat pump to work efficiently or when it is defrosting. In these cases, it will turn on temporarily to help the heat pump and keep the temperature. You do not need to do anything; it will turn off automatically when the temperature rises or defrosting ends.
When to Use Emergency Heat on Heat Pump?
Emergency heat should only be used in emergency situations when your heat pump cannot provide enough heat for your home. Some of the situations, when you may need to use emergency heat are:
Freezing temperatures
In a heat pump, outside air is transferred to the interior. However, there isn’t enough heat for the pump to extract in below-freezing temperatures, causing it to struggle and run continuously without reaching the set temperature. This reduces efficiency and lifespan and increases energy bills. To supplement the heat pump and maintain warmth, use emergency heat when the outside temperature is below 25°F for a short period. Keep in mind that emergency heat can be costly and inefficient to run.
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Damage or malfunction
Heat pumps have components that can be damaged or malfunction, including the compressor, fan, refrigerant, coils, or defrost sensor. If any of these are broken, the heat pump may not work or stop completely. In this case, use emergency heat temporarily until a technician can repair the pump. However, avoid using emergency heat as a permanent solution, as it can mask the problem and worsen the damage. Contact a technician promptly to fix and restore regular operation.
Defrost mode
Heat pumps have a defrost mode to prevent outdoor units from freezing. When frost or ice is detected on the coils, the pump switches to defrost mode, reversing the refrigerant flow to melt the ice. This temporarily stops heating indoor air and may blow cold air. Emergency heat automatically activates for warmth during defrosting. Once defrosting is complete, the emergency heat turns off, and the pump resumes heating.
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How to Avoid Using Emergency Heat?
Emergency heat can be helpful in some situations but can also be costly and inefficient. Therefore, you should avoid using emergency heat as much as possible and only use it when it is absolutely necessary. Some of the ways to avoid using emergency heat are:
Maintain your heat pump
Maintaining your heat pump is crucial to prevent damage or malfunction. Check it monthly, clean or replace the air filter, remove debris or dirt from the outdoor unit, and inspect coils, fans, and wiring for signs of wear. Schedule a professional tune-up once a year to have a technician check, clean, adjust, and fix any issues.
Upgrade your heat pump.
Consider upgrading your old or inefficient heat pump to a newer, more efficient model. New heat pumps have better features and higher efficiency ratings and can save you money and energy.
Insulate your home
Insulating your home is essential to maintaining a comfortable temperature and reducing the heating load on your heat pump. Check for air leaks or gaps and seal them with caulk, weatherstripping, or foam. Add insulation to your attic, basement, or crawl space, and use curtains, blinds, or shades to cover your windows.
Is Emergency Heat more expensive to run?
It’s important to note that emergency heat is more costly to run than your regular heat pump or furnace, as it consumes more energy. It should only be used in emergency situations, such as when your heat pump or furnace is malfunctioning or frozen, and you need to keep your home warm until it can be fixed. Otherwise, you’ll waste energy and money and potentially damage your system, so avoiding using emergency heat unnecessarily is best.
Switching your Heat Pump to Emergency Heat can Cause:
High energy bills: Emergency heat uses more energy than regular heat pumps, relying on less efficient electric resistance heaters or gas/oil furnaces, resulting in higher bills. Use it only in emergencies and switch back to a regular heat pump ASAP.
Taxing your system: Emergency heat bypasses your heat pump and uses a secondary source that can cause your system to work harder and reduce its lifespan. Also, it can worsen any existing issues with your heat pump. Remember to check your heat pump for problems before using emergency heat.
Auxiliary Heat vs. Emergency Heat
Auxiliary heat and emergency heat are two settings on your thermostat that can help you heat your home when your heat pump is not working well. Auxiliary heat is a secondary heat source that turns on automatically when your heat pump cannot keep up with the cold outside temperature or when it is defrosting. On the other hand, emergency heat is a backup heat source that you need to turn on manually when your heat pump is broken or frozen, and you need heat until it is fixed.
It’s important to note that auxiliary heat is more efficient and cheaper than emergency heat. Therefore, it’s recommended to use auxiliary heat whenever possible and save emergency heat for actual emergencies only.
Final Words ~ When to Use Emergency Heat on Heat Pump
Emergency heat is a secondary heating source that can supplement or replace your heat pump when it cannot provide enough heat for your home. It can be helpful in some situations, such as freezing temperatures, damage or malfunction, or defrost mode. However, emergency heat can also be expensive and inefficient and should only be used in emergencies. Avoid using emergency heat as much as possible and only use it when absolutely necessary. You should also maintain your heat pump to improve the efficiency and performance of your heat pump and reduce the need for emergency heat.
