Vaillant Ecomax 835E

The boiler was installed 5 years ago & apart from minor problems with low pressure in the system the boiler has performed well. At the beginning of the year the pump needed replacing & the receipt said that the divertor valve was also replaced (no charge to me). Over the last couple of weeks the boiler has shut off with a low pressure indication & despite trying to use the internal filling loop & an external one the pressure gauge would not go above 1.2bar. Oddly the PRV activated twice last week but the gauge still read low which indicated a problem with the gauge. The water board checked the mains pressure and got 2.8 bar on a garden tap with 16 litres/min flow rate.
The heating & hot water have still been working until today when I had a Vaillant approved engineer from the company who installed the boiler try to carry out a service (as they have every year since installation.
He found the following faults - expansion vessel full of water, Pressure gauge not working, PRV valve needs replacing, internal rubber connecting hose perished & divertor valve possibly stuck mainly open to heating.
I was quoted £420 to replace the faulty parts & service the boiler (not including the divertor), as foolishly I never renewed by boiler warranty insurance. The boiler now appears to be circulating in reverse by pumping through the return pipe & the hot water runs hot for about 30 seconds then gradually goes cold.
I thought Vaillant boilers were reliable but it looks like I got a dud one. Has anyone got any views on whether it is a better option to replace the boiler 9possibly with an Ecotec 831/7) or try to get this one working

If u don't mind paying around £1500 (what I charge) for a new boiler then yes I'd recommend getting a new vaillant ecotec pro 28. You could go for an ecotec plus 28 or 32 kw but that would be extra expense. That new boiler shouldn't give you any issues as the boilers vaillant are making now are brilliant and fault free. Or you could pay to have it repaired and possibly take out insurance cover with either vaillant or what I'd recommend an individual service agent. We do full boiler cover and a service for 130 plus vat to give you an idea

If ur a service agent what's a 28 an 32 plus?? U surely mean 24 31 or 37 plus !

smoggy60 said:

I thought Vaillant boilers were reliable but it looks like I got a dud one.

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yes they are but yours is connected to a dirty system and hasnt been properly maintained. Vaillant will fix it for around £260.