Hot water in my shower comes and goes.

[Simincrowe]

I have a Vaillant Eco tec 28 which was fitted just under 3 years ago. After working fine until a couple of months ago The hot water in my shower runs fine for 3-4 minutes then runs cold. the hot water returns after about 30 seconds or so but a few minutes later it happens again. I had an engineer service the boiler, he then changed the flow filter and I have just replaced the whole shower mixer tap unit and the shower head and the hot water is still cutting off after about 3 -4 minutes in the shower. The engineer has also cleaned the heat exchanger and replaced the diverter valve. Do you have any idea what it could be? What can i do? I'd appreciate your help.

 

[ohmagain]

Could be a split in the diaphragm, had similar problem some time ago and looks like you've tried the other options

 

[AGAS]

 

[AGAS]

I have a Vaillant Eco tec 28 which was fitted just under 3 years ago. After working fine until a couple of months ago The hot water in my shower runs fine for 3-4 minutes then runs cold. the hot water returns after about 30 seconds or so but a few minutes later it happens again. I had an engineer service the boiler, he then changed the flow filter and I have just replaced the whole shower mixer tap unit and the shower head and the hot water is still cutting off after about 3 -4 minutes in the shower. The engineer has also cleaned the heat exchanger and replaced the diverter valve. Do you have any idea what it could be? What can i do? I'd appreciate your help.

what u can do is get a different engineer

 

[dilalio]

So how much did it cost to not solve the problem?

 

[dilalio]

Try turning off the cold feed to the boiler and opening a hot tap. If the water doesn't die down as pipes empty then you are getting crossover somewhere - probably at your shower valve, even if new, rule this out before proceeding further.

 

[Simincrowe]

Thanks for the responses - and yes I will get a new engineer

Could be a split in the diaphragm, had similar problem some time ago and looks like you've tried the other options

This sounds like something we haven't tried - so thank you. I will ask my engineer about that. How much should replacing something like that cost?

 

[Steelmasons]

Thanks for the responses - and yes I will get a new engineer

Could be a split in the diaphragm, had similar problem some time ago and looks like you've tried the other options

This sounds like something we haven't tried - so thank you. I will ask my engineer about that. How much should replacing something like that cost?

Good luck with replacing a diaphragm on these boilers.

 

[Simincrowe]

I don't know the first thing about boilers which is why I am on this forum - I don't know what a diaphragm is or why it should mean I have hot water in the bathroom sink but not in the shower. Any further information would be really helpful. Thanks.

 

[AGAS]

Good luck with replacing a diaphragm on these boilers.

just what i thought

 

[ohmagain]

I don't know the first thing about boilers which is why I am on this forum - I don't know what a diaphragm is or why it should mean I have hot water in the bathroom sink but not in the shower. Any further information would be really helpful. Thanks.

Ahh must of missed that bit regarding water working fine in the sink, still is a possible with the Diaphram but sounds like it would be a mission to just check, I had a Biasi 24s which was quite easy.
Does the water drop happen if you open a bath tap.
Has the engineer checked for any inline filters on pipes around boiler, and where the ones on the shower checked when changed over?

 

[Agile]

Be aware that when you ask questions on a forum you can get replies from anyone.

Not all are boiler engineers with a good understanding of faults. Or in some cases even what parts are inside boilers.

Tony