While you wait for answers, we may have found some information which could help you.
Click here for Central Heating Not Working DownstairsProblem after changing ch pump on a grundfos pump plan?
baxi 105 HE boiler problem?
grundfos selectric 15-50?
Grundfos Pump Plan wiring Centre part 96437234?
how can I fix my old glow worm central heating boiler model 65-80?
Grundfos 1550 ch pump installation?