Vitodens 200-W combi boilers deliver Passivhaus efficiency in Cardiff
Viessmann Vitodens 200-W gas combi boilers have been installed in 42 new council homes in Cardiff which have been awarded Passivhaus status thanks to their outstanding energy efficiency. The 12 mews houses and 30 flats are designed to be healthier, more thermally efficient and cheaper to heat than ordinary properties.
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Project background
Launched in 2019, Cardiff Living is an ambitious and award-winning ten-year partnership between Cardiff council and national construction and development giant Wates Residential. It aims to improve quality of life in Wales’ capital by providing affordable local routes into high quality, low-carbon housing.
Over 600 new homes out of a planned 1,500 have so far been built under the scheme, in twelve locations across the city. One such development is Aspect Place. Described by Cardiff Council’s Cabinet Member for Housing & Communities as the Council’s “flagship low energy-certified Passivhaus development”, Aspect Place is providing much needed social housing in the leafy and affluent suburb of Heath.
Six of Aspect Place’s 42 properties have been sold through the Council’s assisted home ownership scheme, with the remainder being rented to council tenants.
Exceptional efficiency
All of Aspect Place’s five one-bedroom and 37 two-bedroom homes have been designed and constructed using the principles of Passivhaus, the international standard for outstanding energy efficiency in buildings. They require less energy to heat than normal homes thanks to high levels of insulation, triple glazing and MVHR (Mechanical Ventilation with Heat Recovery).
Each property has also been fitted with a state-of-the-art Vitodens 200-W gas combi boiler from Viessmann.
Although air source heat pumps were considered for the project, the appointed installers, Pearce Elite Plumbing & Heating Ltd of Bridgend, recommended opting for the less costly Vitodens boiler because of its exemplary price/performance ratio and remarkable efficiency. It converts consumed energy into heat cleanly and with almost no losses when paired with a weather compensation sensor, boasting a virtually unbeatable seasonal efficiency level of 96 % (compared to a legal requirement of 92% for new condensing boiler installations), thereby keeping gas bills to an absolute minimum. And, if required, it can automatically adjust its operation for variations in gas quality and the effects of high winds on the flue without any need for engineer intervention.
The highly compact dimensions of the Vitodens boiler was an additional advantage compared to heat pumps, especially given space constraints at the Aspect Place site.
The Vitodens 200-W also has an exceptionally large modulation range of 1:17, enabling it to operate at minimum output of 1.9 kW, a low enough level to heat a Passivhaus home without causing overheating. Furthermore, its integrated weather compensation technology allows it to adjust and modulate the system’s flow temperature in response to changing outside air temperatures for maximum comfort and efficiency. And the boilers are simple to install, operate and maintain, too.
“Because of these properties being so well insulated, air source heat pumps would be something of an overkill here,” said Darren McMahon, Viessmann’s Marketing Director. “The Vitodens 200-W covers the heat requirement perfectly and also provides excellent on-demand hot water performance, which is the main heating need in a Passivhaus home.”