Only getting hot water from bath tap no where else.

[TeddySam154]

I have what seems to be a unusual problem and hope can get some advice. I have a bathroom up Stairs, and a wet room down stairs with toilet and sink, plus sink in kitchen. We have a solar hot water system and gas boiler, it's the type where water goes up to loft through solar panel where it is warmed up then goes back down stairs to a tank in cupboard it kitchen, next to this tank is a gas boiler that heats water up if not hot enough. I hope that makes sense.

Okay so my problem is I can get very hot water from bath tap in bathroom up Stairs, but I can't get any hot water from bathroom sink tap upstairs, bathroom sink downstairs or kitchen sink. It's just cold no matter how long you leave it running, occasionally it will go hot for a few seconds but it will then go straight back to cold. It won't stay hot, other times it won't get hot at all.

It all started after kitchen tap broke ( end of tap fell off) so had to replace tap. We definitely got the right type of tap, we have tried replacing tap thinking. There might be a fault with new tap, but still the same problem. I've tried turning off cold water going to kitchen tap as a test but still no hot water, I tried this on the other sinks to but again no hot water.

Could changing that kitchen tap have affected all sink taps in house or is this just a coincidence.
Also all thought we can get really hot water from bath tap it does drop out and go cold every few minute for a few seconds and it goes cold, making running a bath harder and having a shower impossible as it will be hot then suddenly go cold. This was happening before problems with hot water from sink taps.

Any one have any idea what the problem could be and how to fix, is it most likely the solar system or boiler or could it be kitchen tap causing problem

Any advice much appreciated
Thanks in advance

 

[ShaunCorbs]

Can you isolate the water into the cylinder eg the cold feed to it ?

 

[exedon2]

Take it boiler is a combi? Make model and some pics of your system would be useful.
By the way you have wash hand basins in bathrooms not sinks!

 

[TeddySam154]

I think so will have a look in a minute what will this do?

 

[ShaunCorbs]

Turn this off then open your bath / the one that works confirm it stops

Now try your problem ones and report back

 

[Maryplumb]

Is it a thermal store?

 

[Deleted member 120897]

Have you tried isolating the upstairs taps, to see what happens? Also make/model of boiler as asked previously.

 

[TeddySam154]

Sorry it has taken me so long to reply, I've been very ill. My boiler is a Alpha CD25X. I've attached some photos of boiler. Still having same problem. Had problems with bath tap not getting hot water either now, but water still gets hotter from bath tap than from any other tap.
The weired thing I've noticed recently is that the problem is worse in the Afternoons and Evening than the mornings. In the mornings I can get some hot water but it comes and goes. But Afternoons and evenings you can't .

Any ideas as to what's wrong, Another thing I forgot to mention is just before we started having this problem with getting hot water, I turned on hot tap it made a strange sound and then black water came out. Of tap for a bit before going back to clear. Since then we have had problems with getting hot water.

I am waiting for boiler engineer to come out again to look at boiler they are due to come next week. But want to make sure it isn't something obvious before I waste money on boiler engineer. And want to try and get some idea of what's wrong incase they try to fob me off again.

Thanks again for your help and advice