Seven months ago I had a problem. Radiators upstairs worked perfectly, but the downstairs radiators remained cold. After discussion and research, I decided to replace the CH pump. The system then ran perfectly.
The very same problem has now returned as the heating was fired up for the first time since spring.
I have since, turned off all upstairs radiators and the heat returned to the downstairs radiators. I then partially turned on the upstairs radiators to ‘balance’ the system and all appeared to work well.
I then switched off the central heating, allowed the radiators to cool and switched the heating on again. Oh dear … heat upstairs, nothing downstairs!
Is it possible that the replacement pump may have failed after only 7 months or should I be looking at a different cause of the problem altogether.
Radiators (and pump) have all been bled.
I would be extremely grateful for any advice to help me rectify this situation.