Heat PumpTroubleshooting2026-02-14
Heat Pump Short-Cycling: Causes
A heat pump that turns on and off rapidly may be oversized, low on refrigerant, or have airflow issues.
Short-cycling wears out a heat pump and wastes energy. The causes overlap with furnaces but include refrigerant and sizing.
Common causes
An oversized unit, low refrigerant, a dirty filter or coil restricting airflow, a faulty thermostat, or electrical issues can all cause rapid on/off cycling.
Why fix it
Short-cycling strains the compressor — the most expensive component — so prompt diagnosis protects your investment.
Key takeaways
- Replace dirty filters and clean coils
- Oversizing is a common root cause
- Low refrigerant means a leak to repair
- Protect the compressor — diagnose early
Need help with your heat pump?
Licensed, gas-certified technicians serving Greater Vancouver since 1999. CombiBoiler.ca — A division of ROMA Heating Ltd..
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