BigAl

[BigAl]

Hi guys, Well I am pretty new to this plumbing lark. I have altered my central heating pipework to accommodate new rads with no problem and fitted a kitchen with some carpentry help. The problem I have is that I installed a mixer tap and put a non return valve in the hot water feed but I can pee faster than the hot water runs and my missus is going nuts. Are there different pressure loading on this type of valve?
Cheers
Big Al

 

[Plumbstar Tom]

just checking, is this mixer in the kitchen?

What system are you on and have you made sure its not a high pressure tap needing 1 bar or something?

go on from that wheres the hot water feed from assuming its not the mains

Can you swap the feeds over to see if its the same when its through the cold? (idea here is to eliminate a faulty tap)

 

[ecowarm]

why did you have to put NRV on?
If mixer in kitchen no need for NRV, presuming a WRAS tap

 

[Plumbstar Tom]

unless its single flow. or one of those where its a puill out spout

 

[BigAl]

just checking, is this mixer in the kitchen?

What system are you on and have you made sure its not a high pressure tap needing 1 bar or something?

go on from that wheres the hot water feed from assuming its not the mains

Can you swap the feeds over to see if its the same when its through the cold? (idea here is to eliminate a faulty tap)

Hi Tom, The mixer tap is in the kitchen, it has dual feed and fixed spout, it's a Bristan, not sure what pressure it's supposed to run at. My wife picked it 'cos she liked the look of it!! I don't know what a WRAS is. My hot water tank is combined with a cold water header tank not more than ceiling hieght. A pal said I needed the non return valve. I can easily take it out though.
Regards
Big Al

 

[Plumbstar Tom]

Have a look on there website and match it up, you'll find out if its dual flow from there or not and flow rates you should get

Do you understand me to swap the inlets over? it will eliminate it being a dodgy tap

 

[BigAl]

Hi Tom,
I will have a look on their web site and also swap the feeds over, it has been like it since new. Probably do it next Monday now, will get back then.
Cheerrs
Big Al

 

[BigAl]

Re: Mixer Tap

Hi Tom,
Well I have swapped the feeds over and the tap is OK.
I don't know what my system pressure actually is, I was quoted by the water board a minimum pressure of 1.5 bar and a maximum pressure of 9 bar.
On original installation I fitted the flexible tails, which were 10mm. I have now swapped the hot supply for a rigid tail which is 15mm reducing to 10mm for tap entry and I have probably doubled the flow. I now get approx 1.8 litres per min, yet in my bathroom I get 7.5 litres per min from a single supply tap.
I have asked the manufacturer for a tech data sheet, they don't list one for my tap.
I have checked the flow/pressure visually with the hot feed disconnected and the cold water does flow back through the hot supply port, so I would imagine I do need to have the non return valve fitted.
In my second bathroom I also have a bristan mixer tap and the flow from that is just over 3 litres per min, which is adequate. The one thing I have noticed is that there doesn't appear to be a non return valve fitted in the system, is this correct?
Cheers
Big Al

 

[stevetheplumber]

Re: Mixer Tap

you have the wrong type of tap al you need one thats biflow as the preasure diference between hot and cold is to great

 

[BigAl]

Hi Steve, Many thanks for that I will have to replace the damn thing now, lol.
Regards
Allan