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FlowMax · Combi boiler

E01 Ignition / ionization lockout (no flame)

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

What the control is telling you

Burner did not light or flame was not proven by the ionization electrode, so the board locked out. The 120 manual splits causes into 'no spark/ignition' and 'ignites but drops out'.

Applies to: FLOWMAX-90, FLOWMAX-120

Likely causes

  • No gas supply (closed valve, meter off, empty propane tank)
  • Ignition electrode broken or shorted to ground
  • Gas valve faulty
  • Mechanical minimum or slow-ignition setting on the gas valve set too low
  • Gas valve inlet pressure too high (propane units only)
  • Lights then drops out: 120 V line and neutral reversed at the power supply
  • Ionization electrode faulty
  • Ionization electrode lead disconnected

Test and repair steps

  1. Confirm the gas isolation valve under the unit and the gas meter are open and gas is available (or the propane tank is not empty).
  2. Check inlet gas pressure natural gas must be between 7.00 in. WC minimum and 14.00 in. WC maximum; on propane units check the maximum pressure setting is not too high.
  3. Reset by turning the ON/OFF switch off then on; if it still fails, unplug the unit for 30 seconds, plug it back in and retry.
  4. If there is no spark inspect the ignition electrode for cracks or grounding and replace it if damaged.
  5. If there is no gas at the burner during trial: suspect the gas valve; adjust the mechanical minimum / slow-ignition setting if it is too low, otherwise replace the valve.
  6. If the burner lights then goes out verify line and neutral polarity at the 120 V supply and correct it.
  7. Check the ionization electrode lead is connected; inspect the electrode and replace it if faulty.
  8. On first start-up air in the gas line can cause repeated lockouts: the unit tries 3 times; wait about 3 minutes between reset attempts.
  9. Warning: Gas work only by a qualified gas technician; leak-test all gas connections after any repair.

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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.

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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.