Combi boiler delivers hot water then luke warm

[spiritusuk]

My mother has a 10 yr old Vaillant Ecomax boiler and a service contract with British Gas.

She's had quite a few problems with the boiler over the years, often recurring, such as leaks, loss of water pressure, cool radiators etc

More recently the boiler now doesn't deliver constant hot water. It runs hot for a few mins but then I can see the water temperature dropping rapidly on the boiler until it settles at around 62 degree. Closing the tap and opening shortly after gives a bit more hot water but not for long.

Can anyone advise what we should be telling British Gas as I'm starting to lose confidence in their ability to service the boiler properly ?

 

[picasso]

Do the rads heat up when you run the hot water ?

 

[spiritusuk]

Yes.

I have checked the water temp on her boiler as the hot water is running. It seems incapable of maintaining the temperature. When the hot water tap is opened the temp will rise to whatever we have set it as maximum on the boiler e.g. 75 degrees but then it falls rapidly to 65 or lower.

 

[picasso]

I am not an expert on vaillants so you might get different advice from the resident vaillant gurus but I would be looking at the diverter valve not going fully to the hot water position.

 

[easyflow]

I would go for a blocked secondary heat exchanger.

 

[chrispalmer1977]

That would be my first guess too.... however, if the rads get hot when HW is run, could be diverter? Or even both, but doubtful.

 

[spiritusuk]

British Gas man was here for an hour on Saturday and said he would order new parts. Came today and has so far been here over 3 hours !

He's mentioned the heat plate was blocked (possibly exchange but forgive me as my vocabulary when it comes to boilers is non-existent).

He's coming again tomorrow as the boiler has developed a leak whilst he's been working on it !

He's mentioned that there is a lot of sludge in the boiler which is causing the problems. He asked if we had had it power flushed which we had about a year ago but I get the impression that if you get someone other than British Gas to do the power flush then they're sceptical, even dismissive, as to what you have had done.

Starting to sense the guy's frustration with the job......

He's also mentioned the piping needs replacing as we have plastic pipes and the diameter is quite a bit smaller than a standard copper pipe system. He's also said essentially that we need a new boiler.

Not great news and frustrating as we've had a BG annual service only a month ago and no similar recommendations were made at that time.

 

[AGAS]

He's also said essentially that we need a new boiler.

did he say why for that decision , apart from sludge ( power flush ) ??

 

[picasso]

Oh well cant win them all.

 

[spiritusuk]

did he say why for that decision , apart from sludge ( power flush ) ??

Basically because of the sludge. He commented that due to the narrow diameter of the plastic piping he wasn't sure if a power flush would actually help

 

[chrispalmer1977]

Queue sales pitch for BG powerflush! What a load of bulshit!

 

[chrispalmer1977]

Sounds like he's slightly incompetent too!

 

[spiritusuk]

Queue sales pitch for BG powerflush! What a load of bulshit!

On his first visit he conceded that BG are expensive when it comes to power flushing but now that things have started to go t*ts up with the repair job he's fallen back to BG's default position of blaming the boiler problem on the lack of a power flush-the fact we have had it done by a third party doesn't seem to sway them.

It's actually a bit depressing for me and my mother as we put our trust in them but so often feel that they're not exactly sure what the problem is and resort to naming possible faults without coming out and saying it categorically is this or that. Perhaps it's not that easy for them to do, I don't know, but if they said once you've had your power flush with BG and the problems still exist then we will resolve the problem for you free of charge..........sadly that guarantee is never given and we have to take our chances spending a lot of money on something that may not fix the problem.

 

[chrispalmer1977]

So has he replaced the DHW heat ex?? 'Cos that what he needs to do!

 

[spiritusuk]

So has he replaced the DHW heat ex?? 'Cos that what he needs to do!

I'll find out today.....hopefully. Unfortunately, I'm back at work today so won't be there when he attends. If recent history is anything to go by then he will scribble a couple of words on a form and ask my mum to sign it