Thermostatic Shower Valve

[aerialman]

Firstly , hello to everyone.
Your site looks crammed with very useful tips.

Right , here goes................
I have just had a thermostatic shower valve fitted into my new shower room and when turning the valve on (to get a shower) the water runs freezing cold ....forever. The strange thing is , if the unit is off , and hot water is poured over the valve for...say 10 mins (to heat the valve up) .....when starting the valve up again , it works!!!
The shower room is situated downstairs , with a combi boiler feeding it (worcester greenstahr HE) and cold water tank in loft (semi detached house)

All normal taps in house work fine and produce bundles of hot water even while the shower is running (cold) at the same time.

Could it be a faulty valve or maybe too much cold pressure?

By the way , i'm no expert on plumbing (very basic)

Any info would be most gratefully received.
Thanks in advance. Carl

 

[Agile]

What did the plumber who fitted it say?

Can you check to see if the HW in is on the correct port???

I suspect not!

Tony

 

[aerialman]

Hi Agile , the plumber is my uncle and he's 110% sure that the hot water is connected to hot water and same for cold water etc.

I'm new to thermostatic... do they take a while to 'get going , warm-up' ? or is it pretty much instantaneous (well as quick as the water from the combi boiler takes to get to the valve)?

Further checks to do with my uncle tomorrow , so we'll see.

 

[PlanetThanet]

Quote
The shower room is situated downstairs , with a combi boiler feeding it (worcester greenstahr HE) and cold water tank in loft (semi detached house)



Would that have something to do with it?

Thanet.

 

[dal5band]

Seems to me that the hot should only get cut-off when the shower output becomes too hot not the other way round !!

- either there is some sort of adjustment on the valve that needs setting.
- the cold pressure is stopping the hot from running - are there check valves in the feeds ?
- The boiler is not coming on because there is not enough flow on the hot side. Do you have isolating valves - turn the cold to the shower off to see what happens.