Method for controlling air and gas proportions to a gas boiler

摘要

The gas/air control system automatically adjusts the proportions according to any changing draught conditions by maintaining the combustion temperature with alterations to the air blast pressure and the gas demand level. The gas supply to the boiler burner (105) is controlled by a valve (101), control unit (103), an igniter (107) and infra-red sensor (109). A fan (115) provides forced air and a heat exchanger (111) provides the output hot water. An infra-red sensor measures the flame temperature and signals the control unit which adjusts the forced air draught according to prevailing draught conditions and gas flow rate.