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Every year nearly 1 million people need to replace their gas boiler and from April 1st 2005 a change to the Building Regulations will affect every single one of them.

What the new regulation will require is that any new boiler fitted after the April 1 watershed is of the high efficiency ‘condensing type’. Condensing boilers operate at efficiencies of 96% so that they make significant energy savings over conventional boilers; typically 20% or more.

Are they as reliable?

One of the major concerns held by many homeowners, and indeed plumbers and heating engineers is that condensing boilers are a ‘new’ technology and that they are not as reliable as the conventional type of gas boiler. In some cases they are right to be concerned. Some local authorities that have been fitting gas condensing boilers for the last few years in a bid to save energy have been forced to replace the boilers within just three years – not much a product lifespan. In fact this is a lifespan that is just ½ that of many conventional boilers.

Why is this? It is all down to the construction of the boiler. Many boilers feature aluminium heat exchangers which when they come into contact with the condensate produced by condensing boilers will corrode and eventually fail.

Viessmann is German boiler manufacturer and one of the largest suppliers of boilers in Europe. All Viessmann condensing boilers have stainless steel construction, and most importantly, a stainless steel heat exchanger. With over 15 years of experience and 800,000 boilers in the field Viessmann has an unrivalled track record in condensing technology and this has led to its decision to use stainless steel throughout its range since it alone can ensure a 100% corrosion free performance. This confidence in the durability of stainless is matched with the boilers’ guarantee. There is a ten year parts warranty on the boiler heat exchanger against corrosion.

Stewart Purchase, managing director of Viessmann UK says: “We believe that by offering a 10 year guarantee on the heat exchanger in our condensing boilers we can allay some of the understandable concerns that homeowners may have over the reliability of condensing boilers. In the 15 years we have been producing condensing boilers, we have never had a boiler fail because the heat exchanger has corroded. Replacing the heat exchanger in a boiler is the single most expensive fault that can occur and often leads to boilers being condemned. We are the only manufacturer offering such a guarantee.”

Stewart adds: “Homeowners should ask questions about the type of boilers they are buying if they need to replace their boilers after April 1st – after all changing your boiler can be a sizeable investment. Make sure it is from a reputable manufacturer. Ask questions about its construction – this is crucial for identifying its possible lifespan. Also check what guarantees are available to you. While you may not have a choice over fitting a condensing boiler, you certainly do have a choice as to which model you choose.”

How do condensing boilers work?

What are the differences in the new boilers? They work very much like existing boilers, in either conventional or combis, but they take the extra 15% of efficiency normally lost up the flue and use it within the boiler. This causes water vapour to condense within the boiler and a small drain, looking like an overflow from your plumbing, is fitted to run this away.

For further information call Viessmann on 01952 675000,


For further information contact:
Fiona Pavely (
Shelan Communications
Tel: 020 8805 6098

Notes to editors:

Other information available on request:-
• Picture of boilers in situ as well as heat exchanger and burner shots
• FAQ’s to ask your installer
• How to save more money on your bills with weather compensating controls
• More in depth information on how condensing boilers work

This press release was distributed by ResponseSource Press Release Wire on behalf of Shelan Communications in the following categories: Home & Garden, Environment & Nature, Construction & Property, for more information visit