My CH system is pumping over into the header tank. I have searched through the old posts on the subject and the general wisdom seems to be:-
Top of overflow pipe not high enough above level of water in tank
Corrosion
Too much pump pressure.
I don't think it's corrosion because the house has several zones (some with newish radiators) and all cause the problem
I will obviously be doing what I can with the levels but there's only about another foot of roofspace available. The water level is a bit high so I'll lower that. At the moment there is about 18" of differential - might get it to 3'.
I am suspicious of the pump which is a Grundfos Alpha 15/60 (two years old) - when it was new I seem to remember that wherever you set the adjuster it moved to an equilibrium position whereas now it stays where you put it - can the pressure detector mechaism fail or get blocked by crud - so that it jams on max speed?
Also the overflow pipework is only 15mm - will that make a difference?
Just to add, it didn't do this last year but it is now filling my loft with steam and wife is not happy
All ideas gratefully received.
Top of overflow pipe not high enough above level of water in tank
Corrosion
Too much pump pressure.
I don't think it's corrosion because the house has several zones (some with newish radiators) and all cause the problem
I will obviously be doing what I can with the levels but there's only about another foot of roofspace available. The water level is a bit high so I'll lower that. At the moment there is about 18" of differential - might get it to 3'.
I am suspicious of the pump which is a Grundfos Alpha 15/60 (two years old) - when it was new I seem to remember that wherever you set the adjuster it moved to an equilibrium position whereas now it stays where you put it - can the pressure detector mechaism fail or get blocked by crud - so that it jams on max speed?
Also the overflow pipework is only 15mm - will that make a difference?
Just to add, it didn't do this last year but it is now filling my loft with steam and wife is not happy
All ideas gratefully received.