How to mend Boiler Pcb Vaillant

Vaillant igniting issue ( domestic ) not CH?

my vaillant boiler is saying a code com on it ?

Vaillant ecotec 831 plus?

how to fix water pressure its down at bottom of grey part?

Hot water comes and goes!?

Problem with the pressure in combi boiler?

Vaillant ecomax 828/2 e water pressure sensor?

can i replace my Potterton EP2 2 way programmer with a Center EHE0200361 RF?

Vaillant condensing boiler ecoTEC plus?

how do I vent the heat exchanger?

Vaillant ecotec plus 630?

Vaillant Ecotech Plus 831 F22 fault?

Vailliant turbo max plus 824e?

Boiler over pressure on the hot-water side?

Why is heating on at night?

How do I fix f22 error on my Vaillent Ecotec Plus boiler?

Advice?

Vaillant VCW-Sine18 T3WFH Lights but then goes off after 5 Min?

vaillant ecoTEC plus boiler fault code - how to fix?

Vaillant vcw gb242 eh central heating problem?

Valiant thermostat , BMU-Err ?

Vaillant eco plus 531 boiler?

Valliant Eco tec 28?

my boiler will no work?

No hot water, intermittent when air temp drops?

Vaillant Thermocompact Fault?

What does f.25 mean?

Vaillant F22 fault?

Vaillant 828E - no hot water?

how do I rectify the fault as detailed below?