I tried shutting down all the upstairs radiators but still didn't get any heat downstairs. I'll try your suggestion at one of the downstairs rads. This is driving me mad trying to figure it out. I was convinced it was going to be the pump but that's definately spinning😡
Dual pipe system
Think I'm going to have to lift all the floorboards to check the pipe work. I wander if perhaps a flow has accidentally been connected to return. Would that stop the heat?
I recently moved a radiator downstairs from one wall to another and since then the rads downstairs don't work. I have a combi boiler in the loft with 4 rads upstairs and two down. The upstairs gets very hot but nothing down. I've bled all the rads and completely drained the whole system and...