I have a conventional type of central heating system, consisiting of a Potterton floor standing boiler, a Grundfos 15-50 pump, a Honeywell motorised valve and an unvented hot water cylinder. There are seven radiators in the system (6 with microbore and 1 with 15mm pipe). The
original motorised valve (2 wire) has been replaced on many occasions as has the pump. The problem is, every year around about this time when i am using the central heating, the heating comes on and the radiators get hot but the rooms do not heat up, i have checked one of the rooms and the temp was 16 deg after the heating had been on for 4 hours. I have replaced the motorised valve (connecting only 2 wires) in the past and this has cured the problem. Similarly i have replaced the pump in the past and this has cured the problem. I have bled the radiators and everything worked ok 2 days ago, but this morning its back to the rads being hot but not heating the rooms. Does anybody have any ideas as to a solution? i was going to replace the valve again but it means digging up 2 of my slate tiles in the kitchen (again) and i would like to avoid this. I would say at this point that 3 days ago the system wasnt working and then i heard gurgline from the big rad in the living room and then 5 mins later the rooms were heating up - could this be an air problem? and if so what would be the best solution to fix this?
original motorised valve (2 wire) has been replaced on many occasions as has the pump. The problem is, every year around about this time when i am using the central heating, the heating comes on and the radiators get hot but the rooms do not heat up, i have checked one of the rooms and the temp was 16 deg after the heating had been on for 4 hours. I have replaced the motorised valve (connecting only 2 wires) in the past and this has cured the problem. Similarly i have replaced the pump in the past and this has cured the problem. I have bled the radiators and everything worked ok 2 days ago, but this morning its back to the rads being hot but not heating the rooms. Does anybody have any ideas as to a solution? i was going to replace the valve again but it means digging up 2 of my slate tiles in the kitchen (again) and i would like to avoid this. I would say at this point that 3 days ago the system wasnt working and then i heard gurgline from the big rad in the living room and then 5 mins later the rooms were heating up - could this be an air problem? and if so what would be the best solution to fix this?
