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Have you ever glanced at your thermostat and noticed that your heat pump is set to auxiliary heating? This secondary heating system isn’t meant to run all the time, but it will switch on in a few specific situations. Understanding why your auxiliary system has switched on can help you troubleshoot your heat pump and find ways to save on energy bills. Depending on your situation, auxiliary heat can switch on for one or more of these reasons.

Your Heat Pump Is Rushing to Heat Up Your Home Quickly

The main purpose of your auxiliary setting is to help out your heat pump when you need warmth quickly. Heat pumps tend to work slowly and steadily. They don’t churn out huge blasts of warmth all at once, so they can’t raise the temperature by several degrees in a just few minutes.

Therefore, heat pumps include an auxiliary setting that helps bring temperatures to a comfortable level. If you suddenly turn your heat up a couple of degrees, the auxiliary heating will kick on. Usually, it just runs until your desired temperature is reached, and then the main heat pump maintains this heat.

Typically, your auxiliary heat only needs to run for a half hour or so. However, since it does use a little extra electricity, some homeowners don’t like this to happen. If you want to prevent sudden changes from turning on your auxiliary heating, a smart thermostat can be helpful. These devices can be scheduled to warm your home to a temperature by a certain time, so they can warm up the home more slowly and avoid the need for auxiliary heat.

It’s Too Cold for Your Heat Pump to Work Properly

Your auxiliary heat can switch on whenever your heat pump alone cannot manage your heating needs. In some cases, this is due to outside temperatures. Heat pumps work by taking heat from outside and moving it into your home. As temperatures drop, there is less heat for your pump to extract. This can make it struggle to keep your house warm, so your auxiliary heat will kick on to help out.

This cause for frequent auxiliary heating is uncommon. It only happens when temperatures outside are too cold for your heat pump to work by itself. Since modern heat pumps are so efficient, your auxiliary won’t usually need to switch on unless temperatures dip below 40 degrees Fahrenheit.

Your System Is Defrosting

If your heat pump is in the middle of a defrost cycle, auxiliary heating will turn on. Defrost cycles are necessary whenever you have too much ice building up on the outdoor condenser. Ice buildup is normal during winter, but it can keep your pump from working efficiently. To solve this problem, your system will run hot refrigerant through the condenser to thaw out the ice.

While this is happening, your heat pump will be sending all its warmth outside. To ensure your home still stays comfortable during a defrost cycle, your auxiliary heat will kick on. The average heat pump defrost cycle only takes somewhere between five and 15 minutes, so this usually isn’t a major inconvenience. Just keep in mind that during extreme weather, your heat pump may need to defrost every hour or so.

Your Heat Pump Is Undersized

Most heat pumps are set up to start running the auxiliary heat if the heat pump has run for a set amount of time without reaching the desired temperature. This can cause problems if you accidentally got an undersized heat pump. When your heat pump is too small for your living space, it can end up running for hours without warming your home.

Your system may then try to compensate by running your auxiliary heat. If your auxiliary heat is running nonstop even though your heat pump is in good condition and it’s not too cold outside, it might be the wrong size.

Ultimately, your heat pump running on auxiliary heat isn’t usually a huge cause for concern. However, it does burn more energy, so if it happens frequently, you might want to get your system checked out. Texas Pride is here to help Houston residents with all sorts of heat pump repairs. We also provide furnace and air conditioning repair, installation, and maintenance. Our other services include indoor air quality solutions and commercial systems. Give us a call at Texas Pride today to learn more or to set up an appointment.

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