Back Wash Hairdressing Sinks

[al_buckley]

I have 3 new backwash hairdressing sinks in the school where I work. They are each supplied via a hot and cold water supply, which then goes through a regulator to control the temperature. The water then comes out of there splits and goes to the hot and cold fittings on the mixer tap. I have plenty of water pressure upto there but very low pressure comming out of the shower head. Any Ideas of how I can rectify this. Maybe just one supply from the regulator to the hot side of the tap, would that work?
Any help would be welcome
Regards
Alan

 

[plumberdarren]

Are the hot and cold equal pressures i.e both mains or tank fed etc ? when you say it comes from the regulator (thermostatic mixer valve) you say it splits to the mixer tap? are you sure there isnt a tee in the cold feed to the regulator that also goes to the mixer cold then the mixed temperature water to the hot on the mixer? If it is as you say then yes one supply to just the hot side would be sufficient.

 

[al_buckley]

Hi Plumberdarren, The cold water is on mains pressure and there is plenty of pressure on the hot as it use to service 6 domestic sinks as the room was formerly a cookery classroom. The cold water only goes to the regulator where it is mixed with the hot. The warm water then splits and goes to the hot and cold connections to the mixer tap. There is no connection from the cold mains directly to the tap. This is a brand new system and the contractors have given up and will no longer reply to our emails or calls. They have tried an extra connection to the hot supply and pumps but nothing has worked. There seems to be plenty of pressure untill it comes out of the tap. Is there a tap available that just controls the flow, not the temperature and feeds a shower head hose from below?
Thanks for your time and trouble in replying
Regards
Alan Buckley

 

[stevetheplumber]

why would you have two taps fed from the same supply normal way is hot and cold to mixer mixed supply to hot tap and cold to cold tap from a tee before the mixer
all taps controll flow and not preasure

 

[PLUMB-KING]

The cold water only goes to the regulator where it is mixed with the hot. The warm water then splits and goes to the hot and cold connections to the mixer tap. There is no connection from the cold mains directly to the tap.
Regards
Alan Buckley

TMV ( temperature mixing valve ) may have water restrictors or have double check valves. Which may slow down the flow/pressure. The way I've always piped TMV valve is like this.

Hot to TMV + cold to TMV = hot+cold mix, then connect mixed feed to hot side of tap. Pipe cold feed to tap directly from mains before mixer.

Are the taps piped with flex hoses ? there could be a kink in them or slightly squashed..?

 

[Blackcatgas]

Take a picture of the pipe work when your back at work next week Alan, as said it doesnt sound right.

 

[tamz]

Phone the council.

Btw pressure and flow are different things.

 

[fagsanbooz]

As the other guys have said, it sounds like it's not connected correctly.
Some of the TMV's have 'strainers' in the hot & cold legs before the check valves, only a thought that this would definately slow the flow and if they've piped it up incorrectly whats the chances they 'flushed it' properly before TMV's? Only a thought but cannot believe they've left it like it!!