how do I rectify the fault as detailed below?
Problem with the pressure in combi boiler?
Vaillant Thermocompact Fault?
Vaillant Ecotech Plus 831 F22 fault?
can i replace my Potterton EP2 2 way programmer with a Center EHE0200361 RF?
Vaillant ecotec 831 plus?
vaillant ecoTEC plus boiler fault code - how to fix?
how do I vent the heat exchanger?
No hot water, intermittent when air temp drops?
Vaillant igniting issue ( domestic ) not CH?
How do I fix f22 error on my Vaillent Ecotec Plus boiler?
Vaillant F22 fault?