Help - Bath/shower triple valve issue - cold water eliminating hot water.

[olfrog]

Hi peeps,

I bought this concealed triple shower/bath valve about 9 months ago: S9 Triple Concealed Shower Valve with Square Plate

I had to turn the combi boiler off for a week whilst i installed new radiators in the flat. When i turned the boiler back on after a week, the valve seems to have gone weird. Basically, the cold water flow is eliminating the hot water flow - i.e. the cold water pressure is so much higher so hot water cannot get through. The only way i can run a bath or shower is to turn the cold water off using the service valve.

Despite this, all the mixer taps in the flat work fine (i.e. the cold water pressure does not prevent hot water coming through). So it must be a problem with this, rather than with the hot pressure?

I'm on a direct system, and I've attached a photo of the back of the valve (when i was fitting so some of the pipes are missing).

Is there something wrong with the thermostatic part? On this one, there is no dial etc, like i have seen on more expensive thermostatic valves (indeed i did wonder whether this actually is one!)

Thanks a real lot for any suggestions you may have!

Ol

 

[WHPES]

If your hot and cold taps elsewhere in the house are similar pressures, you've probably got some debris down the pipes, else could the check valves be stuck?

 

[olfrog]

Thanks WHPES,

But if it was either of those, then when i turned down the cold using the service valve, the hot still would not work, no? Whereas the hot does work, pretty much to the same flow as before.

If it is inside and i have to take apart, does anybody have a link to a guide to what will be inside? All i remember, as you can see in the photo, is a fairly solid piece of brass!

 

[WHPES]

I would start by opening up the check valves and seeing if the hot one is jammed. It may only be partly blocked. If you take the front plate of the shower, are there 2 large round slotted caps to unfasten? All the check valves and filters are usually behind those. Try that first.

 

[olfrog]

Thanks WHPES. I have opened the check valve and although there was a small bit of PTFE tape (see in the second photo), nothing else, and when i run the mixer at full heat, it still only comes out as 'fairly warm'.

What should i try next? I thought that i should look at the thermostatic cartridge. But (see the third photo) i can't get it out. I thought, perhaps wrongly, that i should use the adjustables on the only part of it that looks like a nut. but it will not budge (and i do not want to break it).

WHPES: should i be looking at the cartridge next, and if so, am i trying to open the right bit?

*Lesson for all*: make sure you get an instruction book from suppliers!!!

 

[PlumbBobBob]

if you take the circlip off the middle spindle you should be able to open it up