Heating appliance

摘要

A domestic combined heat and power system comprising a Stirling engine ( 1 ) and water heater in the form of a supplementary burner ( 17 ). The exhaust gas from the Stirling engine is used to preheat combustible gas entering the Stirling engine and subsequently used to heat the water. The water heater ( 15 ) has a helical water duct ( 41 ) towards the periphery of a housing ( 39 ). Separate parts of this duct are heated, in series, by the exhaust gas from the Stirling engine and the supplementary burner ( 17 ) firing radially outwardly through the helical duct.