how do I rectify the fault as detailed below?
Vaillant 828E - no hot water?
how to fix water pressure its down at bottom of grey part?
Hot water comes and goes!?
Valiant thermostat , BMU-Err ?
Vaillant vcw gb242 eh central heating problem?
No hot water, intermittent when air temp drops?
How do I fix f22 error on my Vaillent Ecotec Plus boiler?
resetting thermostatat?