09:04 AM

What’s “Emergency” or “AUX” Heat and How Can You Manage It?

Heating systems in north Georgia get a workout when it’s extremely cold outside. That doesn’t mean your electric bill has to skyrocket.

Many homes use heat pumps to keep you warm in the winter and cool in the summer. When it’s extremely cold, you may notice your thermostat displaying “AUX” – which stands for “auxiliary heat.” Some systems may display “auxiliary heat” while others may show “emergency heat.” In these cases, the additional heat source is activated automatically by your heat pump. If you manually change the heat source, this is called “emergency heat” on many thermostats. 

Depending on your heat pump system, auxiliary and emergency heat can cost about 2-5 times as much as running normal heat. Though it’s necessary for a heat pump to operate with auxiliary heat at times, you can take steps to reduce how frequently it’s automatically used.

Keep your thermostat set at 68 degrees. Once the normal heat and auxiliary heat in your unit meet your thermostat’s set temperature, your HVAC stops running. Keeping your thermostat at a lower, regulated temperature will reduce the amount of heat your heat pump has to create. In turn, it uses less auxiliary heat, which is more expensive to use.

Raise the temperature gradually. If you raise the temperature of your thermostat more than two degrees at a time when it’s extremely cold outside, your heat pump will not be able reach the set temperature quickly. It may default to using auxiliary heat for additional help to raise the temperature in your home.

Don’t use the emergency setting. Even if temperatures plunge, don’t change the thermostat from the normal heat setting. In the emergency mode, only the electric heat strips in the system are operational. Relying on heat strips for an extended period of time can dramatically increase your electric bill. Use the emergency setting only when there’s an actual emergency, such as when the heat pump compressor fails.

Do regular maintenance. During a maintenance check, a HVAC professional will inspect your heat pump to ensure it’s operating optimally, including during extremely cold weather. Regular maintenance can help catch any potential problems before they become a costly repair.