What Does Auxiliary Heat on My Thermostat Mean?

During colder temperatures, you may notice your thermostat will say “Aux heat” but what exactly does this mean, and is it a bad thing? Baggett Heating and Cooling has all the information you need to know about auxiliary heat.

Extremely cold weather requires your HVAC unit to work harder to maintain your comfortable indoor temperature. The auxiliary heat feature of your electric pump is a necessary and normal sequence of operations.

When the outdoor temperature drops below the home’s balance point (typically about 30-35 degrees here in Clarksville, TN), auxiliary heat is automatically activated to supplement the heat pump to maintain the thermostat’s set point. Once the outdoor temperature rises, the auxiliary heat deactivates and the system returns to running in normal heat pump mode. 

The auxiliary heat mode can also be activated when you raise your thermostat more than 2 degrees, and your heat pump cannot meet the heating demand quickly enough. This will happen regardless of the outdoor temperature. 

Auxiliary heat is not bad, it is a critical mechanism that keeps your home at a comfortable temperature when the heat pump can not do the job alone. The only downside to your system using auxiliary heat mode is the potential for higher utility bills when this mode is activated for an extended period of time.

This video explains the process and the cause for the increase in utility bills.

This is different from emergency heat mode, which has to be turned on manually and is to be used in emergency situations such as malfunction or freezing rain. 

To help prevent any malfunction during these winter months and maintain a comfortable indoor temperature, Baggett recommends regular maintenance performed on your HVAC system. Regular maintenance is best for your equipment and also it protects warranty coverage as well. Learn more about routine maintenance and join Baggett’s Preferred Customer Maintenance Club.

Baggett Heating & Cooling has served the Clarksville/Montgomery County area for over 40 years. Contact us by phone, text, or email.