My combi boiler has a Grundfos 15-50 pump. The pump started making unusual noises intermittently and varied in volume. Central heating first and now hot water have stopped working. Hot water did work for a while when I ran the hot water taps at a low volume. I have drained the boiler - water brown in colour. I have also removed the pump head by unscrewing the 4 allen key screw. (Thanks Mickyg for your advice so far). Thought this might allow me to see if there was dirt jamming the pump or limiting the water flow. Having removed the pump head (which just seams to be the electrics),I see I have very little to work with as the impeller etc.. are still incased . I can see through the whole in the front that there is dirt (black grit) in the pump. but how do I get into it to clean it??? or can I??? Have tried to remove the pump itself but I can't budge the nuts.
Fyi the boiler is a Protherm 80e - 7 years old
Fyi the boiler is a Protherm 80e - 7 years old