How to mend Vaillant Gb 242

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

Vailliant turbo max plus 824e?

how do I rectify the fault as detailed below?

Advice?

Vaillant eco plus 531 boiler?

Vaillant ecotec 831 plus?

Valliant Eco tec 28?

how do I vent the heat exchanger?

Vaillant condensing boiler ecoTEC plus?

my boiler will no work?

Hot water comes and goes!?

No hot water, intermittent when air temp drops?

What does f.25 mean?

Boiler over pressure on the hot-water side?

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

Vaillant 828E - no hot water?

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

Vaillant vcw gb242 eh central heating problem?

Problem with the pressure in combi boiler?

Vaillant ecotec plus 630?

Vaillant Ecotech Plus 831 F22 fault?

Vaillant F22 fault?

Why is heating on at night?

Vaillant igniting issue ( domestic ) not CH?

Vaillant Thermocompact Fault?

Valiant thermostat , BMU-Err ?

vaillant ecoTEC plus boiler fault code - how to fix?

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

my vaillant boiler is saying a code com on it ?

Vaillant ecomax 828/2 e water pressure sensor?