I've laid wet UFH in the new extension (suspended floor) as follows:
1) 3 loops (about 80m each) in the zone. 2) 2 port valves for 3 zones on the flows (UFH, upstairs rads, downstairs rads).
The pressure test indicates no leaks in any of the loops.
When the valve to the UFH is closed, the pressure indicated on the manifold gauge drops to zero over a period of time. The boiler pressure remains at a steady 1.5 Bar. As soon as the valve is opened, the UFH manifold gauge pressure goes back up to 1.5. The zones are operating and heating effectively aside from this.
One thing I haven't examined yet is the impact of the CH zones running when the UFH valve is closed i.e. does it drop when the CH zone valves are open and the boiler is firing.
Can anyone suggest other avenues of investigation or perhaps a theory on what may be happening?
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