glow-worm flexicom 15hx boiler

[janbee]

the boiler sometimes flashes an F22 fault. The manual is of no help and the engineer doesn't know what it is. We always re-set it and all's ok but it still comes back from time to time. It's only a year old and otherwise fine. Can anyone advise what fault F22 is? Thank you

[matt1e]

hi jan
F22 is Low Water pressure or Ignition temperature rise to slow

likely causes are

Not enough water in the system.
Central Heating Flow or Return
Thermistor wires loose, faulty, trapped.
Central Heating Flow or Return Thermistor not connected to pipe correctly.
Air in the system.
Faulty pump or pump speed to fast.

This info should help your engineer

[janbee]

Thank you so much matt1e. That is a huge help and I'll pass the info to the engineer at his next visit. You're a star.
Thanks again

[glowwormer]

F22 would more than likely be trapped air in the system, it could be possible the pump is weakening but doubtful, basically it is down to bad circulation

[janbee]

thanks glowwormer. I'll pass on all info to the engineer next time he visits, in the new year. Many thanks for all info received from you both. I'm very grateful.
Happy Christmas to you glowwormer and to Matt1e

[JHtaylor]

My condensing boiler was showing this fault during the very cold weather. Turns out you can get it if the pipe going to the drain is blocked. In this case with ice. So a couple of kettle of boiling water poured on the pipe cured it.