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FlowMax · Combi boiler

E42 Fan speed control board fault

High severity FlowMax condensing combi (FLOWMAX-90/120)

What the control is telling you

The fan speed (fan) printed circuit board has failed.

Applies to: FLOWMAX-90, FLOWMAX-120

Likely causes

  • Fan control PCB faulty

Test and repair steps

  1. Turn off power and check the connections between the fan and its control board.
  2. Replace the fan printed circuit board.
  3. Restart and confirm the fan runs and the code clears.

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Source: FlowMax FLOWMAX-120 Instruction Manual, 6.10 Troubleshooting table, p.66; FlowMax FLOWMAX-120 Instruction Manual, 6.11 Diagnostics error code list, p.67; FlowMax FLOWMAX-90 User Manual, Diagnostics - Error codes, p.8-9. 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.