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Outdoor unit won't start, 24 V present at contactor coil
What is going on
Possible causes and checks for: outdoor unit won't start, 24 v present at contactor coil.
Likely causes
- Contactor coil open (infinite Ω). Also check fuses, breakers, thermostat
Check in this order
- Replace contactor. (32C) p.876 [850]
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Source: General HVAC service practice — verify per model. Written in our own words; check the manual for your exact model.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.