1302697 Heating air and water; unit heaters MYSON HEAT EXCHANGERS Ltd and WEST MIDLANDS GAS BOARD 11 June 1970 [11 March 1969] 12748/69 Headings F4A and F4V A heating unit supplying both domestic hot water and heated air for space heating has upper and lower box-like sections 1 and 2 comprising angle-iron frames 3, 4 carrying removable panels. Upper section 1 includes boiler 5 supplied with air through grille 27, gas through pipes 8, 10 and valve 9, and having a water jacket with flow and return connections 6, 7 supplying hot water to taps, &c. Pump 14 circulates hot water from the water jacket through heat exchanger 13 in the lower section 2 via primary flow pipe 12 and return pipe 22. Air is drawn in through grille 34 in a panel of section 2 by fan 15 and is blown over the heat exchanger 13 and out through outlets 16 and duct 17 extending vertically through both sections 1, 2. A secondary flow connection may be made downstream of pump 14 supplying radiators through a small-bore circuit and a corresponding return connection made in return pipe 22. Expansion tank 35 may be included in a pressurized system.