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Locks out — oil but no ignition

What is going on

Possible causes and checks for: locks out — oil but no ignition.

Likely causes

  • Electrodes mispositioned
  • Cracked insulators
  • Worn/loose/dirty ignition wires
  • Transformer/igniter dead
  • Primary wires bad
  • Low line voltage. No-spark list also: loose wiring, bad transformer, low voltage, cracked insulator, carbonized electrodes, gap too wide/close

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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.