Unfortunately I'm falling at the first hurdle here, I've tried venting the pump but nothing is coming out of it.
Also the system I have doesn't allow just CH to be set. It's either just HW or HW and CH. The motorised valve just controls flow in to the CH system, there is nothing to prevent the flow through the water tank.
I've had another look at the setuo today. From the F&E tank in the loft a pipe comes down in the airing cupboard and through the pump.
On the other side of the pump is a "T" piece, one side to the motorised valve for controlling the CH and the other to the hot water tank
I'm assuming that the feed goes through the hot water tank heater then to the boiler downstairs. On the return side I can see the pipe coming back up with a connection across to the feed (above the pump) and then in to the loft as the expansion.
I've removed the pump to check it worked OK and it seems fine to me. With the pump removed I opened the valve above it, expecting to see water coming down from the feed tank. However there is nothing coming through. Does this suggest a blockage between the F&E tank and the pump or am I missing something?
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