Hot water from all taps except kitchen cold.

[armyash]

Hi, I have been asked to look at a Ln issue this evening.

Customer said she has hot water coming from all cold taps as well as the hot taps. Except the kitchen cold tap-this is fine.

Ive asked if she has had any work done recently and she said something about a new boiler but she is elderly and sounded a bit confused. I'm assuming the cold taps that are running hot are fed from a cwst and kitchen is off mains which is why it's OK.

I'm going to check the cwst first and see what the water temp is like in there and check the cylinder stat.

What else would you be thinking about if you had this issue?

Thanks

 

[JCplumb]

If all but the kitchen tap are tank fed cold then first thing to check would be temp of water in cwst as you suggest. This makes sense as the kitchen tap is the only one that has to be mains fed.
Could also be hot/cold crossover at a mixer tap/shower, if they're both tank fed the higher head would win. But I think you're onto a winner looking at the cwst first.

 

[armyash]

I went there earlier this evening. old thermostatic shower which isnt being used. The outlet has been capped. Bat/shower mixer and a sink mixer. No iso valves anywhere. The hot water coming from the cold taps is hot not lukewarm.

I had a look in the loft and the water in the tank was warm (not hot), I could see the hot coming back in to the tank.

I'm going back tomorrow evening to cap the shower supplies and fit nrv's to the kitchen and bath hot supplies. I might not need to fit on one the bath as the cold is from the tank.

Does that sound right?

 

[Best]

New mixer tap with mains cold could be faulty (maybe only can be kitchen in your job?)
Or coil in cylinder gone if heating is vented type and with f&e tank higher than cwt.

 

[armyash]

The shower is mains fed also. F and E sat on same platform as cwst.

None of the mixer taps are new. Could be cylinder coil actually. I didnt check that. I'm going back tomorrow and will check that first.

 

[Best]

The shower is mains fed also. F and E sat on same platform as cwst.

None of the mixer taps are new. Could be cylinder coil actually. I didnt check that. I'm going back tomorrow and will check that first.

With tanks being on same base, the f&e tank would overflow first if coil in cylinder gone, so probably rule that out.
Looks like it is kitchen or shower mixer, or a blending valve faulty

 

[armyash]

Thanks for the advice. I'll update tomorrow if i find anything else.

 

[armyash]

It was the shower