This modern detached house is heated by a wood gasification boiler and a solar thermal collector with an oil-fired boiler providing backup. The owner has access to free timber and has virtually eliminated any cost of fuel for heating his house.
A 25 kW EcoAngus Super wood gasification boiler is linked to a 1500 litre Akvair Solar Plus accumulator tank via a pressurised circuit. A Laddomat 21-60 maintains the efficiency of combustion within the boiler and regulates the rate at which the store is charged. The circuit includes a 150 litre expansion vessel.
Protection against overheating is provided by a thermal safety valve which, if the temperature in the store charging circuit reaches 95°C, will open to admit cold water through a ‘quench’ coil in the boiler jacket.
Between April and Oct when the boiler is not in use a 60-tube solar thermal collector maintains temperature in the Akvair via dual solar coils which in turn ensures an ample supply of domestic hot water.
The existing oil-fired boiler was retained and connected to the Akvair to provide backup and convenience when the wood boiler is not in use.