Where to fit non return valves

[gardener1214388]

Non return valves in kitchens and bathrooms
Where should they be fitted ?
e.g. hot water to basin, mixer taps
hot water to bidet, mixer taps
cold water to basin, mixer taps
cold water to cistern
cold water to shower, electric.

Fit them before the isolating valve ?

Does anyone make a non return valve incorporating also an isolation valve; on unit ?

 

[PrenticeBoyofDerry]

They are not required where the taps have the required air gaps.
You would only really need them on bidets and outside taps.

They are used to prevent contamination to potable water, so generally not needed on hot water taps. But in some commercial installs they may be found on central heating pipes also on domestic on boiler filling loop.

And yes there are check valves with isolation.

If you where to install one, I would personally install before service valves.

 

[Newboy]

For mains supply pipework:

Should be fitted on mixer taps connected where the H&C mix within the body of the tap rather than having separate channels.
Must be fitted where the tap has an extendable section/hose/sprayhead i.e. for washing off plates etc.
Must be fitted to shower supplies where the hose is not restrained and can rest either in the bath or shower tray.

The non-return valves should be fitted so that the function can be tested - in an ideal world

supply pipe/isolator/drain-cock/check-valve/drain-cock/appliance feed

 

[Agile]

Sounds like you are a student!

Quite correct though!

Send Prentice back to school!

Tony

 

[PrenticeBoyofDerry]

I did mention air gaps and don't mixers have backflow prevention integrated?
I'll get my satchel!

 

[Newboy]

Sounds like you are a student!

A bit to old for that I'm afraid - does experience count?

 

[holty]

Filling loops work out cheap as they come with double check and isolating valve all in one. And an added valve if needed somewhere else. Not the crappy filling loops though with single isolation.