I have a rather large wet UFH system. Water is flowing around the system, but I don't get any (or minimal) hot water injecting from the primary boiler flow into the ufh system. this means the mix temp never gets above 20 degrees.
I think that the ufh system's pressure might be too high which is causing it to backflow into the t junction where the mix occurs and then this water gets backfilled into the system, backing up the hot water from the boiler.
I've tried fiddling with the diverter valve, but it's so fiddly that half a degree and primary loop goes from cold after the divert flow to red hot!
Pic below if it helps.
I think that I need to reduce the pressure of UFH system but other than that, no idea.
I think that the ufh system's pressure might be too high which is causing it to backflow into the t junction where the mix occurs and then this water gets backfilled into the system, backing up the hot water from the boiler.
I've tried fiddling with the diverter valve, but it's so fiddly that half a degree and primary loop goes from cold after the divert flow to red hot!
Pic below if it helps.
I think that I need to reduce the pressure of UFH system but other than that, no idea.
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