Overflow from big tank in loft pouring out water!!

[rubblelfc]

I had this problem in the middle of last year but I thought it was solved by installing a non return valve to my mixer shower!!

The other day there I went to go in a shower but the hot water wasn't very hot so I couldn't go in it. I thought this was because I used the hot water for a good bit that day but the next day I went to go in the shower early on after my hot water was timed to come on but the water was slightly hotter but not hot enough. I then came home from work and noticed that my overflow was pouring the water out like a running tap. I am getting really sick of it and any help is much appreciated.
I have checked the thermostat and it seems to be working fine.

 

[Puddle]

Are we saying old supply to shower on mains and hot from tank ? if so very bad plumbing practice and will only cause problems

As if both from tank ,as should be and non return valve broke,it would not cause over flow problem

 

[rubblelfc]

Cold to the shower is from the tank above in the loft but the hot is from the cylinder tank.

 

[Plumbstar Tom]

thats correctly fitted then

any other mixer products fitted to the hot water cylinder?

The non return valve may have failed again

 

[rubblelfc]

I have got a mixer tap in the kitchen as well so I'll probably have to fit a valve there as well.

I have been told that my coil in the cylinder could be an issue as well but I'm quite confused with the whole thing to be honest!!

 

[Plumbstar Tom]

best get a plumber in then

Normally if its the coil in the tank you will get dirty coloured hot water

yeh pop one on kitchen tap

 

[rubblelfc]

Thanks Tom,

The water is just normal colour but I'll check the non return valve in the bathroom and will put one on in the kitchen and keep my fingers crossed.

 

[Plumbstar Tom]

its what my bet is on

Kitchen tap will be on mains cold water as you dont want to be drinking tank water