We have been having ‘issues’ with our central heating system.
It is a standard setup, with modern Baxi boiler, hot water cylinder, numerous radiators on a 2 pipe system (feed and return), with a 3 port motorised valve to direct hot water either through the cylinder or to radiators (or both ).
Recently, the downstairs radiators have not been getting warm at all, whilst the upstairs have worked OK though and also the hot water.
The other day I had a look into the reason for this malfunction, as it will only be getting colder from now on.
The problem lay at the door or the motorised valve actuator (Honeywell 40003916-003), so I replaced it last night. The old one didn’t do very much when the heating was switched on – little or no movement of the motor, and making a few noises that I didn’t recognise. Whilst the actuator was off, I also removed the valve cover and cleaned the valve internal parts of any crud that had accumulated, and the port entrances too.
Anyhow, The valve then starts working and such. Still no better than before though for the downstairs rads.
As the pump had been making a few strange noises, I also changed that, it was also getting quite hot too (although this may be normal).
Still no improvement !
I have gone round each radiator to bleed them – nothing but water came out.
I have also switched every rad off at their tap, and turned each one on sequentially – all worked and got hot when individually turned on. So I started turning more on, so the rads I had on were, hall, front room, kitchen, bathroom, front bedroom, bedroom 2 all stayed on hot.
Then I switched on the shower room and landing rads, and after a while the downstairs rads went cold.
I went to work, and asked the wife to switch off the shower room and landing and front bedroom rads to see what effect it had. – still waiting for her to answer.
Anyone got any ideas, as it’s beginning to pee me off.