Viessmann 200 and 222 fault fault E8
Ionization current lies outside the permissible range
Gas boilerWhat it means
Burner in fault mode due to detailed code 189: ionization current outside permissible range
Likely causes
- Flue gas temperature exceeded monitoring limit
- Gas supply issue
- Incorrect gas type allocation
- Ionization electrode distance or contamination issue
Where to start
- Check flue gas temperature sensor
- Check gas supply (gas pressure and gas flow limiter)
- Check gas train and connecting lead
The full answer, free
- 4 more checks in order
- How to put it right, step by step
- The manual page for this fault (page 1), right under the answer
Safety: Isolate gas and power before you open the case. If you have been into the gas side, do a tightness test, and a combustion and flue check before you hand back. Gas Safe (UK) or RGI (Ireland) work only.
From the Viessmann manual for the 200 and 222 fault. Check the model on the data plate before you order parts.
Other Viessmann 200 and 222 fault fault codes
- 2Gas supply no/low gas pressure detected
- 33Power supply voltage is below minimal operating level; internal fuse failure
- 8Flue gas temperature has exceeded the monitoring limit
- E3Heat transfer too low during calibration
- EAIonization current outside permissible range during calibration (deviation too great)
- EBRepeated flame loss during calibration
- EEAt burner start, flame signal is missing or too weak
- EFFlame is lost immediately after it has built (during the safety time)
- F1Maximum flue gas temperature exceeded 230°F (110°C) limit
- F2Fixed high limit switch open (activated)
- F3Flame signal already present at burner start
- F9Fan speed too low during burner start
- FAFan not at standstill
- FCGas valve faulty or faulty modulation valve control; or vent system blocked
- FEDamaged or incorrect boiler coding card or main PCB
- FFInternal fault or reset button R blocked