While you wait for answers, we may have found some information which could help you.
Click here for Hot Water Minutes
boiler wont stay alight?
no blue light from the bosch boiler?
Grundfos UPS 15 45 x18 central heating pump?
LPG bosch w-135?
Bosch 30CDi how do I restore the pressure. ?
Bosch W275 water heater, diaphragm leaking?