Viessmann condensing  combi boilers use high performance heat exchangers. These cool the flue gases before they escape through the chimney, to the extent that the water vapour contained in these gases is deliberately condensed. This releases additional heat which is transferred into the heating system.

With this technology, a gas condensing boiler achieves a standard seasonal efficiency [to DIN] of up to 98 % (relative to Hs). Condensing boilers are therefore particularly energy efficient, looking after both your wallet and the environment.

Please note that all our prices are excluding VAT & up to 10 years guarantee. Our prices are for a like for like boilers, i.e. Combination to combination, system to system or conventional to conventional. If you need to convert from system to combination or vice versa then there is a conversion charge on top of the current prices.