What Is Auxiliary Heat? 2024 Guide

Auxiliary heat, or "aux heat," is an essential feature in many heating systems, especially for those who live in colder climates. If you're wondering what auxiliary heat is, when it's used, and how it impacts your home heating, this guide will provide all the answers you need!

What Is Auxiliary Heat?

Auxiliary heat is a secondary heating system that kicks in when your primary heating source, usually a heat pump, can't keep up with the demand. Heat pumps are great at pulling heat from the outside air to warm your home, but they can struggle when the temperature drops too low. That's when auxiliary heat steps in to provide extra warmth.

Auxiliary heat most often comes from electric resistance heating coils or a gas furnace. It provides a quick boost of heat to maintain the desired temperature in your home. You'll often see the "AUX" indicator light up on your thermostat when auxiliary heat is active.

When Does Auxiliary Heat Turn On?

Auxiliary heat turns on automatically when your primary heating system can't keep up. This usually happens when:

• Outdoor temperatures drop too low: Heat pumps become less effective when cold outside. The heat pump might need help to pull enough heat from the air when the outdoor temperature is too low. Auxiliary heat turns on to provide additional warmth.
• Quick temperature increase is needed: If you adjust the thermostat to a much higher temperature, auxiliary heat may kick in to speed up the warming process.
• Defrost mode is activated: Heat pumps have a defrost mode to prevent ice buildup on the outdoor unit. The heat pump can't heat your home during this time, so auxiliary heat is used temporarily.

Is Auxiliary Heat Expensive to Use?

Yes, auxiliary heat can be more expensive than your primary heating system. The reason is that auxiliary heat often relies on electric resistance heating, which uses a lot of electricity. Running it for long periods can lead to higher utility bills. However, it's designed to be a backup, so it should only be on some of the time.

To keep costs down, ensure that your heat pump is maintained correctly, and avoid setting the thermostat to very high temperatures quickly. Gradual adjustments can reduce the need for auxiliary heat. Additionally, a home inspection can help identify any inefficiencies in your HVAC system or insulation, further improving energy efficiency and reducing long-term costs.

How Can You Tell If Your Auxiliary Heat Is On?

Many thermostats will display an "AUX" or similar indicator when auxiliary heat is active. This is an excellent way to know when your system uses more energy. If your home suddenly feels warmer and your energy usage increases, it could also indicate that the auxiliary heat is running.

To check, look at your thermostat or consult the manual for your specific heating system. If auxiliary heat frequently turns on when it's not very cold outside, it might be a sign that your heat pump needs maintenance.

What's the Difference Between Auxiliary Heat and Emergency Heat?

Auxiliary heat and emergency heat are often confused, but they are different:

• Auxiliary Heat: This mode kicks in automatically to support the heat pump when needed. It's a regular part of your system's operation.
• Emergency Heat: You manually activate this manual heat pump if it isn't working correctly or fails. Emergency heat bypasses the heat pump entirely, relying solely on the secondary heating system. It's more expensive to run and should only be used when necessary.

Understanding the difference can help you avoid using emergency heat unnecessarily, which can drive up your energy bills.

How Can You Make the Most of Your Heating System?

Here are some tips to get the best performance from your heat pump and auxiliary heat:

• Regular Maintenance: Make sure your heat pump is serviced regularly. Clean filters, clear debris around the outdoor unit, and check for any issues.
• Smart Thermostats: Consider installing a smart thermostat that learns your heating preferences. This can minimize the use of auxiliary heat by adjusting temperatures gradually.
• Proper Insulation: Ensure your home is well-insulated. A well-insulated home retains heat better, reducing the need for auxiliary heat.
• Energy-Efficient Settings: Keep your thermostat at a consistent temperature. Sudden temperature changes can activate auxiliary heat.

When Should You Call a Professional?

If your auxiliary heat runs too often or your energy bills are unusually high, it might be time to call a professional for inspection services. A heating expert can inspect your system, identify any issues, and suggest improvements. They can also advise on upgrading to a more efficient system if needed.

It's essential to have your heating system checked before the winter season starts. Preventive maintenance can help you avoid unexpected problems when the temperatures drop.

Why Is Auxiliary Heat Necessary?

Auxiliary heat is essential because it ensures your home stays warm during freezing weather. Even the best heat pumps have limitations; auxiliary heat is a backup to maintain comfort. Without it, your home could get chilly during extreme weather, and your heat pump could overwork itself, trying to keep up.

Conclusion

Auxiliary heat is a valuable part of many heating systems, providing extra warmth when your heat pump can't do it alone. Knowing how it works and how to manage it can help you keep your home cozy while controlling energy costs. To get the most out of your system, keep an eye on your thermostat, schedule regular maintenance, and make gradual temperature changes.

Need a heating system check-up or advice on optimizing your home's heating? Contact Guardian Angel Inspections today!