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Indoor blower runs, outdoor unit dead

What is going on

Possible causes and checks for: indoor blower runs, outdoor unit dead.

Likely causes

  • Severed thermostat cable, bad transformer, open high-pressure switch, bad stat

Check in this order

  1. Blower running proves line and low voltage at furnace
  2. Inspect low-voltage wiring at condenser
  3. Replace cable. (32D) p.877 [851]

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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.