how do I rectify the fault as detailed below?
Hot water supply?
Water dripping from opening at top of pump?
Boiler over pressure on the hot-water side?
Vaillant eco plus 531 boiler?
how to fix water pressure its down at bottom of grey part?
Vaillant Ecotech Plus 831 F22 fault?
Vaillant ecotec 831 plus?
Vaillant condensing boiler ecoTEC plus?
Vaillant VCW-Sine18 T3WFH Lights but then goes off after 5 Min?
Valiant thermostat , BMU-Err ?
resetting thermostatat?