Furnace AC Compressor Problems — Diagnosis and Repair
Published: July 23, 2026 — BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning — Greater Vancouver, BC
Signs of Compressor Problems
The outdoor unit hums but the compressor does not start, the compressor makes a loud buzzing or grinding noise, the unit short-cycles on the overload protector, the compressor runs but does not cool, or the circuit breaker trips when the compressor tries to start. A failing compressor is the most serious AC issue.
Compressor Repair Costs
Capacitor replacement (compressor not starting): $200-400. Contactor replacement: $200-350. Hard start kit installation: $200-350. Compressor replacement: $1,500-3,500 (includes compressor, labour, refrigerant, and disposal). Most compressors cost $800-2,000 for the part alone.
Replace Compressor or Replace AC?
If the AC is under 8 years old and the compressor is under warranty (most have 6-12 year warranties), replace the compressor — you pay labour only ($800-1,500). If the AC is over 10 years old and out of warranty, replace the entire system ($4,000-7,000). A new system will be more efficient and include a new compressor with a fresh warranty.