1. It's Blowing Lukewarm Air in Heating Mode

A heat pump should deliver air that feels warm — typically 90–100°F at the register. If it's blowing room-temperature or cool air in heating mode, the system may have a refrigerant issue, a reversing valve problem, or a defrost control failure.

2. Ice on the Outdoor Unit (Beyond Normal Defrost)

Heat pumps frost up in cold weather — that's normal, and the defrost cycle handles it. But if the outdoor unit is encased in ice and the defrost cycle isn't clearing it, something is wrong. Don't chip the ice off yourself; call a technician.

3. Unusual Noises

Grinding, squealing, or rattling from the outdoor unit usually means a failing motor bearing, loose component, or debris in the fan. Hissing suggests a refrigerant leak.

4. Short Cycling

If the system turns on and off every few minutes without completing a full heating or cooling cycle, it may be oversized, have a refrigerant issue, or have a failing control board.

5. Higher Energy Bills Without Explanation

A heat pump that's losing efficiency will run longer to maintain setpoint, driving up electricity costs. If your bills have risen without a change in usage habits, schedule a diagnostic.

6. The System Won't Switch Modes

If your heat pump is stuck in heating or cooling mode and won't switch, the reversing valve may be failing. This is a repair — not a replacement — in most cases.

7. It's Been More Than a Year Since a Tune-Up

Heat pumps work year-round (heating and cooling), so they benefit from annual maintenance more than a furnace or AC that only runs seasonally. If it's been over a year, schedule a tune-up before the next season.