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ICP · Furnace

LED off Amber status LED off - no power / blown 3 A fuse

High severity ICP (F/G)9MAE Modulating Furnace

What the control is telling you

The control shows nothing. Usually no 115 V or 24 V at the board, an open door switch, or the 3-amp 24 V fuse is blown.

Applies to: ICP F9MAE / G9MAE modulating variable-speed condensing gas furnaces (060, 080, 100, 120 kBtu/h)

Likely causes

  • Blower door switch open
  • Breaker off / no 115 V at L1-L2
  • Blown 3-amp automotive fuse (24 V short)
  • Failed transformer

Test and repair steps

  1. Warning: Manually closing the door switch exposes live 115 V parts - use caution.
  2. Check the breaker is on and there is 115 V at L1 and L2 on the control.
  3. Make sure the blower door is on and the door switch is closed; confirm 115 V reaches the switch, replace switch if power goes in but not out.
  4. Check for 24 V at SEC-1 and SEC-2; if 115 V is present but no 24 V, replace the transformer.
  5. If the 3-amp fuse is open, replace it with a 3-amp fuse ONLY, then disconnect thermostat leads to find the short in the 24 V wiring.

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Source: ICP (F/G)9MAE Service and Technical Support Manual 440 04 4700 00, Figure 16 Troubleshooting Chart, p.33. Summarized in our own words; check the original manual for your model.

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