[gilford]

Had my bathroom totally re-done before Xmas. Had a Bristan bar valve shower fitted coming directly off the hot water tank (oil central heating). Recently, the water is going cold when we're having a shower, why is that???

I first thought it was the hot water had ran out but if you run the sink or bath taps they are fine??

Could it be the thermostat in the bar valve

Any help appreciated


Cheers

[the whistler]

I would say that it will either be the thermostat gone faulty, or it may be just down to water pressure problems. Your cold water comes in at a much higher pressure than the hot water from the cistern and they need to be balanced. Its usual to fit a pressure reducing valve on the cold supply. Maybe this has gone faulty or your cold water mains pressure may have been increased by your water supply company and upset the balance.

If you have some form of stop tap on the cold supply to the shower, try part closing it to reduce the cold supply. This may help.

You could try posting on www.diynot.com. Thats were all the experts hang out!

[T0MAT01]

Modern showers have an 'anti-scald' device which will basically cut the hot water off if the pressure changes during use... this can happen when someone uses another tap as it could upset the balance which might be the cause.

[gilford]

Sorry to dredge this up again

I reduced the cold water pressure last Sunday after the comments (cheers ) and all has been fine. Just got in from squash and jumped in the shower and it has happened again

The water coming out is cold but if you touch the bar valve its piping hot as it usually is?? This says to me that its the shower at fault, am I right?

I need to know before I go to the supplier and play hell with them

Cheers

[cwick]

I have a similar problem, with mine it seems to be a 'sticky' thermostat cartridge. Every month or so it'll just stop working - the bar valve is nice and hot, but the water is cold. So turn off the supply, pop out the cartridge, clean it up (it tends to have a very fine layer of scale on it, no idea if that's the problem though), put it back together and it's fine for another month.

It only takes a couple of minutes, I keep the box spanner in the bathroom now

[gilford]

Originally Posted by cwick

I have a similar problem, with mine it seems to be a 'sticky' thermostat cartridge. Every month or so it'll just stop working - the bar valve is nice and hot, but the water is cold. So turn off the supply, pop out the cartridge, clean it up (it tends to have a very fine layer of scale on it, no idea if that's the problem though), put it back together and it's fine for another month.

It only takes a couple of minutes, I keep the box spanner in the bathroom now

How do you go about doing that then bud? I'm a plank with these things, thats why I paid a fitter thousands to do it for me

Although he hasn't done a great job now has he......................

[gilford]

Anyone know the easiest way to remove the bar valve?

Cheers

[cwick]

On mine there's a little blanking cover on the end of the temperature knob. Get that off, and there's a screw underneath. Undo it, slide it off. You'll then need a big box spanner, undo the nut holding the cartridge in, and it will then slide out of the bar valve body.

Don't forget to turn to water off first though !

You can always phone Bristan technical support, they're very helpful. I called them about mine when I first moved in, and they sent me a replacement cartridge for nowt just in case it was broken. Top service.

[gilford]

Cheers for that bud

I have only had it a few months so I think I will just take it back and get a new one, saves messing about