Viessmann 200 and 222 fault fault 8

Flue gas temperature has exceeded the monitoring limit

Gas boiler

What it means

Burner in hold/wait state, boiler not displaying fault; refer to coding address 38:XX. Flue gas temperature has exceeded the monitoring limit

Likely causes

  1. Gas supply issue
  2. Incorrect gas type allocation
  3. Ionization electrode distance or contamination issue
  4. Flue gas temperature exceeded monitoring limit

Where to start

  1. Check gas supply (gas pressure and gas flow limiter)
  2. Check gas train and connecting lead
  3. Check allocation of gas type

The full answer, free

  • 4 more checks in order
  • How to put it right, step by step
  • The manual page for this fault (page 3), 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