I have just reviewed this issue for my plumbing and realise that I do not have anything installed (check or stop valves) on my cloakroom mixer tap from B&Q. There is mains on cold and tank on hot. Should I need to fit something here?
Check Valves.
- Thread starter happyhacker
- Start date
A check valve should be put on the cold to prevent any syphonage from the hot going down the cold and into the main, should the main be turned off and drained for any reason.
It's not the end of the world if you don't, and it's up to you if you decide to or not. I personally wouldn't bother.
Hope this helps.
It's not the end of the world if you don't, and it's up to you if you decide to or not. I personally wouldn't bother.
Hope this helps.
uneven pressures should have a single check valve on both supplies.
Thanks, thought - if hot into mains only occurs when the mains tap is OFF then I don't see a problem except that any mains tap turned on in this state may receive hot water if the responsible mixer tap is also turned on!
Hot water certainly won't go into the mains supply pipe!
Hot water certainly won't go into the mains supply pipe!
And whys that then ?
taps, showers etc can still bypass without them being turned on.
I assume that if the mains tap is OFF then it won't allow flow in either direction. Also isn't is a battle against pressure? Our mains is of very high pressure compared with our gravity system.
Interesting that a tap can pass when the taps are OFF. Of course the tap is to supply water to the spout but I would have thought this included stopping water in any direction within the unit! Thanks for the information - I need to know a bit more about tap design.
Interesting that a tap can pass when the taps are OFF. Of course the tap is to supply water to the spout but I would have thought this included stopping water in any direction within the unit! Thanks for the information - I need to know a bit more about tap design.
No but if the water board close it off further down the supply it can backflow.
Take a kitchen monobloc tap remove the spout.
it will have 3 0 rings if the middle one fails the cold mains will pass to the hot gravity.
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