This is less of a question, but more of a list of things we tried to stop the frequent F11, F22 and F25 error codes appearing on our Glow Worm Flexicom HX boiler which would stop it from functioning. We have some big (for UK) rooms with three large radiators in the reception rooms.
- F11, F22 and F25 error codes
- Really noisy central heating pump, runnning flat out
- Cold radiators, especially downstairs, even if upstairs were really hot.
- Moderately hot tap water
- Generally a very cold house especially when outside temps approach zero °C
Solutions we tried which DID NOT work
- Turning up the boiler temp
- Turning up the thermostatic valves for the radiators
- Reducing flow for upstairs radiators to increase flow in downstairs radiators
- Replacing the thermostatic valves with new for the radiators which would not heat up