Temp problem with mixer shower

[grazzauk]

Hi,

I am having a problem with both thermostatic mixer showers in my house.

Both run cold\luke warm when used.

If i turn on the hot tap the water comes out boiling.

Mains pressure is good, and i have 1.5bar indicated on the boiler.

The only way I can get the showers to work properly is to turn on the cold tap on a sink first and leave it running, then turn on the shower....?

I think I may have a pressure problem somewhere?

Equipment is:
Boiler - Ideal Response 120 Combi
Showers - Aqualisa & a Triton.

Any ideas?

Thanks

Graham

 

[Softus]

Equipment is:
Boiler - Ideal Response 120 Combi
Showers - Aqualisa & a Triton.

That's not really very informative.

Any ideas?

Fit a non-return valve on the hot supply to each shower.

 

[diy]

Have they allways been like this.

 

[grazzauk]

no, used to be fine

have a feeling the pressure reducing valve on the mains feed might be broken?

 

[diy]

I think you need to check the incoming cold pressure, is there a gauge on the prv. more than likely the showers are in need of a service and / or replacement cartridges.

 

[grazzauk]

one of the showers is only 3 months old - could the cartridge be faulty so quickly?

Have just done some testing and the gauge on the prv is reading 5bar with no load - if I turn a hot tap on the boiler kicks in it shoots up to 9.5bar....

 

[diy]

it does sound faulty. try reducing the pressure down on the valve ... see what happens at cold kitchen tap.