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User avatar
By Best
#5107
I am wondering if an outside tap is installed without built in check valves, is an existing double check valve above the main stopcock good enough, - or must the supply pipe to the tap have a check valve?

My thinking is the existing check valve will prevent back siphonage into the underground mains supply.
And a back siphonage to the house mains taps etc, is highly unlikely unless a garden hose was to be above the height of house taps.
But I guess “highly unlikely” does not prevent regs
User avatar
By REDSAW
#5108
is it not the location so the back flow cant enter the circulating supply?
i.e. after it 't's to o/s tap?

DC on bib tap :x
User avatar
By Best
#5110
REDSAW wrote:
September 27th, 2018, 1:34 pm
is it not the location so the back flow cant enter the circulating supply?
i.e. after it 't's to o/s tap?

DC on bib tap :x
Yes, I guess there is no other way around the regs other than to have a DC on the pipe to tap, or use a DC tap, which I avoid because of frost damage risk to the valve inside tap.
Job I was thinking of could never have back siphonage unless the customer put the end of hose into something very high up, but regs are regs.
User avatar
By REDSAW
#5113
Best wrote:
September 27th, 2018, 2:40 pm
REDSAW wrote:
September 27th, 2018, 1:34 pm
is it not the location so the back flow cant enter the circulating supply?
i.e. after it 't's to o/s tap?

DC on bib tap :x
Yes, I guess there is no other way around the regs other than to have a DC on the pipe to tap, or use a DC tap, which I avoid because of frost damage risk to the valve inside tap.
Job I was thinking of could never have back siphonage unless the customer put the end of hose into something very high up, but regs are regs.
just stick dcv on cok, tell sustomer to turn off in winter and cover up. if they dont and it jams easy money in spring :lol:
User avatar
By REDSAW
#5300
kozak1968 wrote:
March 17th, 2019, 4:51 pm
Water board are only worried about back flow getting into their mains and not your house.
where as building regs will have you over a barrel if they could be rsed, over a trivial matter like this. :(
User avatar
By REDSAW
#5368
NikIncawn wrote:
May 26th, 2019, 3:07 am
Before I bury the well-to-house line Id like to tap a line of to feed a hydrant in the garden thats about 40/50 feet away from that line. Should I put a check valve in that tap? If so, where would it be best to locate it? Near the hydrant or near the main line?
best of, near or at the hydrant so its maintainable. ;)

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