Worcester & Vailliant Condensing Boilers

8 Jun 2010
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United Kingdom
I'm hoping to get a heat only, boiler, around 28 KW, for an open vented system.

Looking at postings in this forum and elsewhere, I get the impression that
there is a slight preference for Vaillant compared to the equivalent Worcester

My conclusions are -

Vaillants are slightly more reliable,and easier to service. The electrics
are easier to install. OTH the customer service provided by Valliant is very
poor, ie. long waits on the telephone. I'm not sure about the availability of
spares. Vaillants are cheaper, perhaps owing to less advertising?.

Worcester's have the advantage of an excellent customer service, and readily
available spare parts. They are marginally more energy efficient. Their boilers
are guaranteed for two years agianst Vaillant's one year.

The diagnostics provided by the Vaillant boilers are better.

I've seen a posting somewhere on the net saying that Worcesters are less reliable
than they used to be, due to the use of plastic parts instead of metal ones.

I've found that in depth technical information on the Worcesters is easy to
obtain on the net, Vaillant is difficult or impossible.

The companies I've spoken to are equally divided in their preference, and
willing to install either make.

Is there any noticable difference in noise levels?

Looking forward to any comments,and corrections if any of my findings
are wrong.

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I'm in exactly the same position and will be very interested to read the replies to this.....
Approved installers of both companies can offer five year warranties on the boiler, same with Viessmen.

Far as I'm aware both manufacturer's boilers 'out of the box' come with two years warranty on the boilers and the prices of both thier product ranges are broadly similar.

I've no experience with Valliant boilers, there are very few fitted in Glasgow relative to Vokera and Worcester, but I've plenty of experience with Worcester-Bosch who are as good a company for customer service that I've ever dealt with on both a personal and a business basis. I would place them in the John Lewis level of customer service and care to be frank.

I would say however that thier boilers are extremely expensive relative to say the likes of Vokera but personally I like Worcester Bosch boilers and I would fit one in my own home, currently I have a Vokera combi which has given me no trouble what-so-ever in five years and niether did the previous Vokera boiler that I had for the 12 years previous to that.

I'm finding it difficult now, in the current economic climate, to advise customers to go with WB boilers given how expensive they are relative to most other boiler manufacturers in the market but if your looking for really good customer service and back up and are willing to pay a premium for that then go for WB ( WB's service engineers carry something like 97% of the boiler's spares in the van) or go with a cheaper boiler manufacturer and spend the money saved on a BG homecare contract or take your chances and don't :LOL:

A BG or similar contract won't get your boiler working quicker than a manufacturer's engineer will simply becuase the manufacturer's engineer will have the spares with him and fix your boiler on the first visit, most times.

I think WB and the likes of BG employ a priority system for sending engineers out on service visits i.e. no hot water and heating puts you up the list and gets you an engineer out quicker in times of high demand as does your age as does having children/babies and so on.

One of the main differences of both boiler manufacturers is that one uses aluminium heat exchangers (WB) and the other (Valliant) uses stainless steel heat exchangers and depending on who you speak with one is better than the other, the only thing I'm aware of is in this regard is that WB advise the PH in the heating water shouldn't be higher than 8.6, presumably Valliant's advice would be in the opposite direction.

The WB CDI heatcell has been in continuous production for 15 years and carries a 10 year warranty, the WB CDI range is built in Germany and the SI and Junior range is built in the UK. I don't install the SI or Junior ranges only the CDI because, IMO, it's a far better boiler.

The cost of WB spares relative to Vokera is pretty cheap IMO, I have no idea of the cost of Valliant spares.

Bottom line is you pay your money and take your chances......

My Valliant Ecotec Plus is virtually silent and to an amateur (me) it looks better quality than my friends WB.
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My Valliant Ecotec Plus is virtually silent and to an amateur (me) it looks better quality than my friends WB.

Depends on which WB boiler your talking about but the CDI series boilers are the quietest boilers I've heard and I think they are the best looking quality boilers in the market.

The junior and SI series are frankly rubbish looking, I have no opinions on the sound of them.

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