Any Plumbers??

DannyW · 16 Feb 2014 at 20:01

Hi guys, Im fitting a new bathroom and all my taps and shower are the mixer type, the hot water is high pressure fed from my combi boiler

Do it need to fit non-return or double check valves to the hot and cold incoming, I know I need isolating vavles, not sure about the others

thanks

Nightglow · 16 Feb 2014 at 20:15

No, I never have, some mixer taps have them prefitted, but ordinary hot water is low risk, compared to a outside tap.

Only time I have used a non-return or double check valves is for a outside tap, in fact it's a requirement now for a outside tap.

bitslice · 16 Feb 2014 at 21:49

The shower head is supposed to not drop below the outflow pipe on the bath though,
I ignore that as I hate that little holding clip thing for the shower cable.

Nedved11 · 18 Feb 2014 at 22:25

Gets wras book out... If the water mixes in the spout you will Need a return valve. If it's a cheap tap chances are it will. If it's a decent brand it will be separate. If it's fed through at mains pressure fit on hot and cold side as you will get uneven pressure at the tap. For a shower it will mix so fit on both sides.

Mickie · 18 Feb 2014 at 22:50

your hot water is fine and for whatever reason the hot water ever got sucked up into the cold main it would be fine, it obviously wouldnt contaminate the cold water..

not like heating water or dirty bath water getting sucked up into the main if the fire brigade cause back pressure sucking up the mains..

Nedved11 · 18 Feb 2014 at 22:57

Mickie said:
your hot water is fine and for whatever reason the hot water ever got sucked up into the cold main it would be fine, it obviously wouldnt contaminate the cold water..

not like heating water or dirty bath water getting sucked up into the main if the fire brigade cause back pressure sucking up the mains..

On the contrary mate. That's why you fit a check valve to stop contamination of any used water down the water main regardless of if it's dHW. As stated by the wras book check valves on both sides.

Mickie · 18 Feb 2014 at 23:04

Nedved11 said:
On the contrary mate. That's why you fit a check valve to stop contamination of any used water down the water main regardless of if it's dHW. As stated by the wras book check valves on both sides.

hot water from a combi is mains fed, water regs state a check valve isnt required in this situation..

if hot is fed from a tank in the loft which then goes to a mixer tap that mixes hot and cold than a check valve is required..

Nightglow · 19 Feb 2014 at 09:10

Mickie said:
hot water from a combi is mains fed, water regs state a check valve isnt required in this situation..

If hot is fed from a tank in the loft which then goes to a mixer tap that mixes hot and cold than a check valve is required..

+1

DannyW · 20 Feb 2014 at 16:39

Thanks guys

Participant · 20 Feb 2014 at 18:50

Nedved11 said:
On the contrary mate. That's why you fit a check valve to stop contamination of any used water down the water main regardless of if it's dHW. As stated by the wras book check valves on both sides.

Didn't you read the thread title?

Nedved11 · 20 Feb 2014 at 21:59

Participant said:
Didn't you read the thread title?

Hilarious. The wras book is open to interpretation too I'm a belt and braces man myself. Only qualified plumber for a few years and it's the way I do things and had no complaints yet.