Viessmann · Vitodens 100-W combi
63 boiler fault code
Vitodens 100-W type B1KF combi
What 63 means
Flue gas temperature limiter has responded
Emergency guidance
If you smell gas, a CO alarm sounds, anyone feels unwell, or there is an unsafe flame, leave and call 0800 111 999 from outside.
Open the emergency safety guideWhen to contact an engineer
Your boiler has shut down for safety. Don't keep resetting it. Leave it off and get a Gas Safe engineer to check it.
Renting? Report it to your landlord or housing provider first. They are responsible for gas safety and boiler repairs, and the repair should not cost you.
Source and provenance
- Viessmann Vitodens 100-W Installation and service instructions for contractors · chapter 7 “Troubleshooting”, “Fault messages”, code 63, p. 70
installation and service instructions for contractors
6167586 GB · 3/2023