Strange hot water problems

[waccoe]

Hello all, hoping someone might be able to help with some strange goings on with our hot water. We have quite an old condensing boiler which serves an unvented system, which is an albion ultrasteel, that was installed about 5 years ago. We've noticed that some of the taps don't get hot unless another tap is run. E.g. kitchen hot tap wont give out hot water unless the downstairs cloakroom tap is also run. If we have hot water in the kitchen, then turn off the cloakroom tap, the kitchen water will go cold again.

Same thing happens upstairs, basin tap takes minutes to get hot, if turned on full, when it does, if we turn it off, wait a minute, it will be freezing cold again, and have to run it again, full blast to get hot water. It never gets hot if not turned on full.

Bath taps in the same room, wont get hot water unless the basin taps are run.

Does this sound like a non-return-valve problem somewhere, shower perhaps?

Amy ideas or help much appreciated.

 

[igneous]

How far is the hot water cylinder from the outlets (taps) ?

 

[waccoe]

Not far at all, the cyclinder is in the airing cupboard next to the upstairs bathroom tap, but the pipework runs up to the loft and back down again. The puzzling thing is that the downstairs cloakroom next to the kitchen gets hot water fairly quickly, but the kitchen next door, wont get hot water at all unless the cloakroom tap is run.

 

[picasso]

It sounds like a nrv problem, can you isolate the showers for a start?

 

[waccoe]

Thanks, that's what I thought it might be, as the shower has been playing up as well, it's one of those steam showers, take my advice, never ever buy one of those things, nothing but trouble. I can't isolate the shower unfortunately, but it is due for replacement in the next couple of months. I could fit an inline NRV on the shower inlet, in the meantime, which should be quite easy and cheap.