how do I rectify the fault as detailed below?
my boiler will no work?
No hot water, intermittent when air temp drops?
Vaillant Thermocompact Fault?
Vaillant vcw gb242 eh central heating problem?
Valiant thermostat , BMU-Err ?
how to fix water pressure its down at bottom of grey part?
Hot water comes and goes!?
Vaillant eco plus 531 boiler?