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Andrew Smith
Andrew Smith, Plumber
Category: Plumbing
Satisfied Customers: 3776
Experience:  City and Guilds qualified plumber
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I’ve got a potterton promax combi 28 HE a, On heating

Customer Question

I’ve got a potterton promax combi 28 HE a,
On heating demand, the boiler temp rises quite quickly, but doesn’t heat the system. The first radiator gets warm but the return pipe is cold. The pump seems to be running and we have checked for blockages to the first rad but all is good.
We have also checked the filter on the return valve of the boiler. The hot water works fine.
Any ideas ?
Submitted: 4 months ago.
Category: Plumbing
Expert:  Andrew Smith replied 4 months ago.
It sounds like the pump is failing.
Try venting it through the cap on the top and the screw I the front.
How clean is the water in your system?