A 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.