My father has a problem with his central heating system and I'm hoping someone might know what's going on. Here's what he's sent me:-
Went on holiday for 2 weeks C.H. left on with t/stat turned down to
15C, H.W. turned off.
On return t/stat turned to 20 C and H.W. turned on. All seemed O.K.
Next a.m. Boiler started up on C.H. switch on and then cut out on temp after only 2 mins. (system cold). Found air in pipes by circ. pump which is on 1st floor. Opened bleed screw and purged air. Boiler re lit itself and all seemed O.K. except for noise of water moving thro. pipes and rads. Subsequently I am daily having to bleed 1 or more of the rads and also use bleed screw by circ. pump.
When bleeding with the circ pump off I get air out but when it stops I don't get water out as you would expect. Have checked header tank and there is water in, though there is no sign of any change in water level as you may expect as a result of fresh water replacing the air.
There is no sign of water leakage from the system.
Suggestions gratefully received.