Check Valves when and where to fit them

[gardener1214388]

When and where should check valves be fitted and to which pipes (Hot water ? ) and why.

Single Check Valves, Double Check valves, Mixer Taps, I am fitting Abode mixer taps to basin.

 

[Steelmasons]

6 week crash course might be the way forward.

 

[Nozzle]

Fit them where you don't want potentially contaminated water mixing with potable water {should the pressure drop}.

Nozzle

 

[gardener1214388]

6 week crash course might be the way forward.

I thought it was a one year course.

 

[gardener1214388]

Fit them where you don't want potentially contaminated water mixing with potable water {should the pressure drop}.

Nozzle

That's what I thought,....thanks.

 

[Newboy]

Or re-read this thread

//www.diynot.com/diy/threads/non-return-valves-confusing-information.432911/

 

[Madrab]

When it comes to protection against CAT2 Water (hot water) a single check valve is as much as you need.

That being said it all depends on the type of system you have and type of mixer tap. If it's a dual flow mixer then not needed, if it's a single flow (mix in the body) then regs dictate that it should be fitted on the cold side. Abode are very good that way, check their specification sheets for the taps, it will state if it's single or dual flow.
It's rare that the hot pressure would ever be greater than the cold in a working system.

 

[Steelmasons]

It's rare that the hot pressure would ever be greater than the cold in a working system.

Really?????
A good few systems still in use using mains hot water (combi/water heater) with cold being fed via CWSC.

 

[Madrab]

We are talking about check valves and the need for them when using single flow mixer taps. A large percentage of mono/mixer taps are 'in the body' (single flow)mixers and need a balanced supply to work efficiently.

I certainly agree that a lot of systems still use unbalanced supplies though they would usually be fed through individual taps and not through single flow mixers and wouldn't require a check valve at the tap inlet. If they were using single flow mixers with gravity cold and mains hot then the usual unbalanced supply issues could be experienced therefore the design would need to be changed to balanced and the need for a check valve.

I guess I should have added "balanced" into that comment for clarity.

 

[Steelmasons]

No disrespect Madrab but I suspect you don't see many working systems , Google is not always your friend..like so many armchair enthusiast's on this forum..

 

[Madrab]

Non taken Steel, but after 12 years working in Glasgow's old housing stock I've seen my fair share but thanks for the armchair enthusiasts sentiment, I wish life was so relaxed.