Why Is My Heat Pump Blowing Cold Air in Heating Mode?
If you're in Lawrenceville, GA and your heat pump is running but not warming your home, you're not alone. Heat pumps are one of the most efficient heating and cooling systems available — but when something goes wrong, diagnosing the issue can be tricky. This guide walks you through the most common heat pump repair problems and what to do about them.
How a Heat Pump Works
Unlike a furnace, a heat pump doesn't generate heat — it moves heat from the outdoor air into your home. In summer, it reverses and acts as an air conditioner. This dual function makes heat pumps highly efficient but also means there are more potential failure points than a single-function system.
Common Reasons Your Heat Pump Is Blowing Cold Air
1. The System Is in Defrost Mode
Heat pumps periodically run a defrost cycle to melt frost buildup on the outdoor unit. During this short cycle (usually 5–15 minutes), the system temporarily blows cool air. This is normal. If it's happening constantly or lasting much longer, you may have a defrost control issue.
2. Refrigerant Leak
Low refrigerant levels prevent the system from transferring heat effectively. Signs include ice buildup on the outdoor unit, hissing sounds, or significantly reduced heating capacity. Refrigerant recharge and leak repair typically costs between $200 and $500.
3. Faulty Reversing Valve
The reversing valve controls whether the heat pump is in heating or cooling mode. If it gets stuck, the system may stay in cooling mode even when heat is selected. Reversing valve replacement typically runs $300–$600 for parts and labor.
4. Dirty Air Filter
A clogged filter restricts airflow, reducing heating efficiency. If your heat pump seems to be running constantly without warming the home, check and replace the filter first. This is the easiest and cheapest fix — often under $20.
5. Outdoor Unit Issues
Ice buildup, debris, or a failing outdoor fan motor can prevent the heat pump from absorbing heat from the air. Keep the area around your outdoor unit clear of leaves and debris, especially in fall and winter. Fan motor replacement typically costs $200–$400.
6. Auxiliary Heat Not Activating
Most heat pumps in Georgia are paired with auxiliary electric heat strips for very cold days. If the aux heat isn't activating, your home may struggle to reach the set temperature on cold nights. This could be a thermostat, control board, or heat strip issue — typically $150–$400 to diagnose and fix.
Signs You Need Heat Pump Repair in Lawrenceville, GA
- Heat pump is running constantly but not heating
- Strange grinding, squealing, or clicking noises
- Ice forming on the outdoor unit outside of defrost cycles
- Significant spike in electric bills
- System short-cycling (turning on and off frequently)
Heat Pump vs. Furnace: Should You Switch?
If your heat pump requires frequent repairs or is more than 12–15 years old, it may be more cost-effective to replace it. In Georgia's mild winters, heat pumps are often the most efficient choice, but a licensed HVAC technician can help you compare options for heat pump installation in Lawrenceville, GA based on your home's needs and your utility costs.
Schedule Heat Pump Repair in Lawrenceville, GA
Don't suffer through cold nights waiting on a heat pump that won't cooperate. Henson Heating Air and Plumbing provides expert heat pump repair in Lawrenceville, GA, with fast response times and transparent pricing. Whether it's a refrigerant leak, a faulty reversing valve, or an outdoor unit problem, our technicians can diagnose and fix the issue quickly.
Contact us today or visit our Lawrenceville service page to schedule your heat pump repair appointment.
