7 Signs Your Heat Pump Reversing Valve or Defrost Board Is Failing Before a Cold Snap
Don't wait for the first 40-degree night in Pasco or Polk County to find out your heat pump won't switch to Heat. Watch for these 7 warning signs.
How Florida heat pumps switch from cooling to heating
Most homes in Zephyrhills, Plant City, Lakeland, and Land O' Lakes rely on a heat pump rather than a gas furnace. Because the outdoor unit sits in cooling mode 10 months of the year, the reversing valve and defrost control board rarely get tested until the first cold front drops overnight temperatures into the 40s.
7 warning signs to catch before temperatures drop
1. Cold air blowing in Heat mode: The reversing valve solenoid or slider is stuck in cooling mode.
2. Outdoor unit turns into a block of ice: A failed defrost sensor or defrost board prevents the unit from melting frost on damp, chilly mornings.
3. Auxiliary or Emergency Heat stays on: Electric heat strips take over full-time, spiking your winter power bill—see our heat pump aux-heat guide.
4. Loud hissing or clunking at shutdown, 5. Breaker trips on heating startup, 6. Short cycling in Heat mode, and 7. A persistent burnt-dust smell that doesn't fade (covered in our heater smell safety checklist).
24/7 winter heating repair across inland Tampa Bay
Call Cool Breeze Tampa Bay for fast heater and heat pump repair in Zephyrhills, Plant City, Lakeland, and Land O' Lakes.
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