Heat Pump Auxiliary Heat — High Bill Cause in Asheville, NC
'Aux Heat' showing on your thermostat? Quality Mechanical explains why it activates and how to minimize its impact on your WNC energy bills. Proudly serving Asheville & Buncombe County.
Professional Heat Pump Auxiliary Heat — High Bill Cause in Asheville, NC
When you need heat pump auxiliary heat — high bill cause in Asheville, NC, Quality Mechanical & Fireplaces is your local HVAC team. Located just Headquartered here from our Asheville headquarters, we provide fast response times and the same NATE-certified service that Asheville area residents have trusted since 2005.
As our home base since 2005, Quality Mechanical & Fireplaces has proudly served Asheville homeowners and businesses with reliable HVAC services. From the historic homes in Montford to new construction in South Asheville, we know the unique heating and cooling needs of every Asheville neighborhood. Our office on Emma Road means fast response times anywhere in the city.
Auxiliary Heat: What It Means
When your thermostat displays "Aux Heat," your heat pump is receiving supplemental help from its backup heating source — usually electric resistance strips mounted in the air handler. The key distinction from emergency heat is that auxiliary heat operates in tandem with the heat pump rather than replacing it. The heat pump keeps running and pulling warmth from outdoor air while the backup strips bridge the gap between the heat pump's output and your home's demand. A certain amount of auxiliary heat activation is perfectly normal during the coldest days of a WNC winter.
Normal Reasons for Aux Heat to Engage
Three common scenarios trigger auxiliary heat: outdoor temperatures falling below your heat pump's balance point (the threshold where the heat pump alone can no longer keep pace), a defrost cycle running to clear frost from the outdoor coil, and a significant temperature recovery event (for instance, bumping the thermostat up several degrees at once). Brief aux heat usage under these conditions is expected and not a reason for concern.
Aux Heat as a Warning Sign
If the "Aux Heat" indicator remains lit for hours on end, illuminates when outdoor temperatures sit above 35 to 40 degrees, or coincides with a sharp spike in your electric bills, there is an underlying problem. Frequent offenders include low refrigerant levels, a neglected outdoor coil, a malfunctioning reversing valve, an incorrectly programmed balance point on the thermostat, or a heat pump that is undersized relative to your home's heat loss. Any of these conditions forces the system to lean on costly backup heat more than necessary.
Cutting Down on Aux Heat Saves Real Money
Quality Mechanical can tune your heat pump system to minimize auxiliary heat reliance. Our process includes verifying refrigerant charge, cleaning both coils, inspecting the reversing valve, recalibrating the thermostat's balance point, and confirming that the equipment is properly sized. For WNC mountain homes where winter temperatures routinely dip into the teens and twenties, stepping up to a cold climate heat pump can sharply reduce — or even eliminate — dependence on auxiliary strips.
HVAC Challenges in Asheville
Asheville's mix of historic homes in Montford and North Asheville — many built before central HVAC existed — creates unique retrofit challenges. These older homes often have limited ductwork space, uneven heating across floors, and single-pane windows that strain heating systems. Meanwhile, newer South Asheville construction demands properly sized high-efficiency systems to handle the area's 4,400+ heating degree days per year.
Seasonal Tip for Asheville Homeowners
Asheville's elevation means nighttime temperatures can drop into the 20s even in early spring. We recommend keeping your heating system serviced through April and scheduling AC maintenance by mid-May to prepare for the humidity that builds through summer.

Serving Asheville & Buncombe County

Serving Asheville
- Headquartered here from our Asheville office
- Same-day appointments available
- 24/7 emergency response
- NATE-certified technicians
- Free estimates on installations
- Financing available
Neighborhoods We Serve
Montford · West Asheville · Biltmore Village · North Asheville · South Slope · Kenilworth · Grove Park
Need help now?
(828) 845-1974FAQ
Heat Pump Auxiliary Heat — High Bill Cause FAQs
Need Heat Pump Auxiliary Heat — High Bill Cause in Asheville?
Quality Mechanical is Headquartered here away. Call today for fast, professional service.




