handheld bidet - backflow preventer

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gzt

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#1065711 14-Jun-2014 20:22

Aredwood: If you have space to put it somewhere, Get one of these pumps http://www.trademe.co.nz/building-renovation/plumbing-gas/water-cylinders-heaters/auction-740338248.htm Connect the inlet of it so it will take water from the toilet cistern. Then the cistern will be providing backflow prevention. And you could add some cleaners / soap to the toilet cistern if you want to get the nether regions even cleaner that what you could with water alone.

...which will lead you to a situation where you empty the cistern rapidly and have nothing to flush the toilet with.

andrewNZ

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#1065807 14-Jun-2014 23:36

gzt:
Aredwood: If you have space to put it somewhere, Get one of these pumps http://www.trademe.co.nz/building-renovation/plumbing-gas/water-cylinders-heaters/auction-740338248.htm Connect the inlet of it so it will take water from the toilet cistern. Then the cistern will be providing backflow prevention. And you could add some cleaners / soap to the toilet cistern if you want to get the nether regions even cleaner that what you could with water alone.

...which will lead you to a situation where you empty the cistern rapidly and have nothing to flush the toilet with.

Toilet cisterns tend to refill themselves.

greenbone

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#1065955 15-Jun-2014 12:55

some good info, but a lot of concerns about leaving the wash head inside the toilet bowl ... wtf .. that makes about as much sense as storing your toothbrush in the toilet bowl ... not really a valid concern for most people surely

andrewNZ

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#1066020 15-Jun-2014 14:47

greenbone: some good info, but a lot of concerns about leaving the wash head inside the toilet bowl ... wtf .. that makes about as much sense as storing your toothbrush in the toilet bowl ... not really a valid concern for most people surely

I believe it was stated that people do this if (when) it develops a leak. It'd be the obvious solution for a lot of people.

driller2000

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#1066026 15-Jun-2014 15:06

greenbone: some good info, but a lot of concerns about leaving the wash head inside the toilet bowl ... wtf .. that makes about as much sense as storing your toothbrush in the toilet bowl ... not really a valid concern for most people surely

but it's not the only backflow risk - the fact that the bidet handheld washer comes into close proximity with a$$ is a risk

as opposed to e.g. a toilet which has 2 air gaps by virtue of the discharge pipe from the cistern to the bowl and from the filling pipe to the cistern itself

backflow regs for these sort of fittings exist for a reason : /

greenbone

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#1066147 15-Jun-2014 19:18

andrewNZ:
greenbone: some good info, but a lot of concerns about leaving the wash head inside the toilet bowl ... wtf .. that makes about as much sense as storing your toothbrush in the toilet bowl ... not really a valid concern for most people surely

I believe it was stated that people do this if (when) it develops a leak. It'd be the obvious solution for a lot of people.

they come with their own on/off tap ... if it leaks, you turn it off, and it doesnt divert flow from anywhere else, ie. you can still flush the toilet as usual

dropping the wash head into the bowl because it leaks ... youd have to be pretty dumb, lazy and unhygienic to do that

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aquahort

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#1081477 5-Jul-2014 15:04

Im astounded by all the comments by others saying you need a backflow preventor.
The units already have a very powerfull backflow preventor on them, it is the spring loaded handle gun valve for turning it on in first instant, and as soon as your release the handle it shuts tight.
If no pressure in the pipes , then some one out in the street would have to open the mains water supply 150mm diameter pipe to waste and drain the street of water, for it to siphon back. Even then the physics of atmospheric pressure of a siphon from a 3 story building, would not suck the water back via the hose gun valve spring and seat as by design it is a nonreturn valve. Backflow preventors on a averge water system is the biggest con, waste of money.
Ive seen fish factorys have to put backflow preventors on hoses coming down from a ceiling 2.5 meters high, utterly impossible for a siphon to go back up that far, from a open valve, unless there is atlest a 3.5 meters fall going back the other way. One learns about siphoning water in high school.

eracode

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#1081494 5-Jul-2014 15:37

aquahort: Im astounded by all the comments by others saying you need a backflow preventor.
The units already have a very powerfull backflow preventor on them, it is the spring loaded handle gun valve for turning it on in first instant, and as soon as your release the handle it shuts tight.
If no pressure in the pipes , then some one out in the street would have to open the mains water supply 150mm diameter pipe to waste and drain the street of water, for it to siphon back. Even then the physics of atmospheric pressure of a siphon from a 3 story building, would not suck the water back via the hose gun valve spring and seat as by design it is a nonreturn valve. Backflow preventors on a averge water system is the biggest con, waste of money.
Ive seen fish factorys have to put backflow preventors on hoses coming down from a ceiling 2.5 meters high, utterly impossible for a siphon to go back up that far, from a open valve, unless there is atlest a 3.5 meters fall going back the other way. One learns about siphoning water in high school.

I'm often amused by comments put up here by people who have no real knowledge or experience in the subject matter of a thread. Not looking at you, aquahort, quite the opposite - and have probably been guilty of it myself. However that's part of the fun and charm of the GZ community - sorting the wheat from the chaff. The debate's the thing, so long as uninformed advice is not dangerous or worse.

At the other end of the spectrum, there's more often brilliant, expert stuff on here.

Sometimes I just sit and think. Other times I just sit.

aquahort

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#1081535 5-Jul-2014 16:52

One can not connect a Bidet hose to the cistern, that would only dribble out the gun it has absolutely no head pressure, it would not work.
If the gun hand piece leaks, get some one to take it apart and fix, or buy and sit next to toilet a metal toilet brush holder canister that will take a couple of litres of leak water. Failing that just buy another gun/hand piece or as the other writer said turn off the water at the wall.
Regards John

gzt

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#1081599 5-Jul-2014 20:29

greenbone: got a callback from Reece plumbing; their advice is a dual check valve with 25mm air break, p# 104553, rrp $48.50+gst. think i will proceed

aquahort

If that meets the standard it is a very small price to pay. The standards are there to prevent issues in the very rare cases where something almost impossible just happens to occur.

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