My combi boiler, installed around 6 years ago, failed earlier. Heating still works fine, but no hot water. It give a second or two of hot water, and then just cold.
Tried to get hold of a manual or a customer service (to locate someone to repair), and their website (.co.uk) is all but gone... I am sure it was there last time I checked (could be a year or two ago).
Any idea what is going on?
Also, any idea what to look for with the boiler? Pressure is still ok.
Diverter valve or associated electrics. Slight possibility of a blocked heat exchanger, but unlikely.
ISTR Valliant bought Saunier Duval (I could be wrong). I am sure someone on this group can email you a manual if you give the model no.
A part of Glow Worm/Vaillant:
Forgot to mention that water coming out is warmish, not mains-cold.
Also, the boiler seems to switch to hot water when it should - I hear something switching inside as usual, and the display changes to hot water "mode" - i.e. water pressure. assume this the Diverter valve is ok then?
No, that pretty much confirms that the diverter valve is not opening/closing correctly. If you can DIY, they sell a kit to change the internal seals of the valve, or, you can buy a new valve. No idea of the valve cost, but the repair kits are £10 - 30ish. Any decent merchants should be able to get them in.
Thanks for the tip.
Don't think that I will try it myself - happy to DIY pretty much everything apart from plumbing and plastering...
I think the expansion vessel is not happy either - had some problem with pressure dropping last year, had it re-pressurised then, but still pressure dropping slowly, so may need replacing now.
Also a few drops under the boiler once every few weeks - nothing serious, and no logical explanation, but I suppose it is time to have it look into as well now.
Thanks again.
They gave me the relevant contact details though.
They have dropped selling Saunier Duval in the UK. Some models were rebadged Glow Worm/Vaillants.
I now have access to manuals for virtually every boiler
Saunier Duval are now part of Glowworm and use a lot of glowworm parts
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