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Pressurized System Losing Pressure With Newly Installed Worcester 27Kw Boiler

Postby SeanRocks » Thu Nov 03, 2016 12:54 pm


I have recently had a heat only Worcester 27kw regular boiler installed in the roof. Its a pressurized system with mains water fed into an expansion tank into the boiler. If I open the valvues on the expansion tank, I can pressurise up to 1 bar only. Is this what I should expect? My understanding is that this can't go higher than the pressure supplied by the water supplier.

I seem to be losing pressure - dropping to 0.5 bar - over a couple of days. I can't see any signs of leakage from the radiators, pipes feeding taps or elsewhere. What could be causing the drop in pressure?

I will have the installer around on Monday. Are there any questions I should be asking him when he comes? Is there any testing I can do in the mean time to help fault find?

Also, the pipe to the boiler - what size diameter should have been used? I think it is a 20mm diameter pipe?

My stove (all gas and not to dissimilar from this: ... GwodAnAFeA) required a new pipe to be installed. A 10mm pipe was used. Is this correct?

Thank you in advance
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