More than just hot air

Aervent-Lindab offers higher BER ratings through SAP approval on heat recovery ventilation.

Under today’s testing regime the efficiency of a good heat recovery ventilation (HRV) unit may not be fully recognised, leading to a building energy rating (BER) lower than deserved. HRV supplier Aervent-Lindab is now offering a way for the efficiency to be properly recognised through Appendix Q to the Standard Assessment Procedure (SAP), the British government's recommended method system for measuring the energy rating of residential dwellings.

“At the moment we have three SAP Appendix Q approved units,” said Aervent’s Dave Cussen.

The models are as follows: two heat recovery ventilation units, the HRE 350 and the LoWatt HR 204DC, and an extraction unit called the Multispeed, Multivent. All three are manufactured by Vent Axia.

Instead of using the default figure for HRV in the DEAP software, the Vent Axia uni’s can use the UK’s SAP calculation, thus improving the overall rating of the building: “When you’re doing BER calculations you can use the SAP data,” said Cussen.

“Traditionally heat recovery units had pretty inefficient motors ” he said, “[but] the DC (direct current) units will use thirty to sixty per cent less energy.” Cussen also said that the heat exchanger in the units is up to 90 per cent efficient.

“The HRE 350 is for buildings of 110 to approximately 280 square metres and is tested for a kitchen and seven additional wet rooms. The HR 204DC is typically used in apartments and small houses, up to 100 square metres and is tested for a kitchen and two additional wet rooms.”

According to Cussen, using DC motors confers additional benefits on the homeowner: “One big factor in the DC technology is that it lasts on average up to three times longer - Vent Axia offers a five year warranty on any of its DC motors.”

Cussen believes that in a short time DC motors will be a standard feature: “The lifetime cost is a lot less,” he said. “Aervent will always promote units with DC motors.”

More details on Aervent’s range of Vent Axia systems can be found at: http://aervent.com. Information on SAP Appendix Q is available at: http://www.sap-appendixq.org.uk.

Last modified on Tuesday, 20 May 2008 14:48