What does f.25 mean?
my vaillant boiler is saying a code com on it ?
Vaillant Ecotech Plus 831 F22 fault?
Boiler over pressure on the hot-water side?
Vaillant condensing boiler ecoTEC plus?
how to fix water pressure its down at bottom of grey part?
my boiler will no work?
Vaillant ecotec plus 630?
vaillant ecoTEC plus boiler fault code - how to fix?
No hot water, intermittent when air temp drops?
Problem with the pressure in combi boiler?
Vaillant 828E - no hot water?
can i replace my Potterton EP2 2 way programmer with a Center EHE0200361 RF?
Vaillant VCW-Sine18 T3WFH Lights but then goes off after 5 Min?
how do I rectify the fault as detailed below?