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Skytech · Gas fireplace

4 Beeps Every Second Sensor safety - flame sensed before ignition

Medium severity AF-4000

What the control is telling you

The pilot flame sensor sees a flame when an ignition sequence starts, or the sensor is shorted to ground.

Applies to: Skytech AF-4000 MOD-1, AF-4000 MOD A and SMART MOD remote modules (used on many fireplace brands)

Likely causes

  • Pilot flame actually present with the valve off (valve not closing)
  • Flame sensor shorted to ground
  • Failed pilot assembly or module

Test and repair steps

  1. Clear it press OFF, then ON to retry a normal ignition.
  2. Check whether a pilot flame is still there with the valve turned OFF; if yes, the valve must be replaced.
  3. Check the flame sensor and its lead for a short to ground.
  4. Replace the pilot assembly, then the module if the fault stays.

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Source: Skytech Audible Alerts & Error Codes for AF-4000 MOD-1 / MOD A / SMART MOD, p.2-3. Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

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.