method for regulating the residual content of oxygen in the exhaust gases of combustion plants to fan and device to implement said method

摘要

An output-controlled blower-type firing installation is operated by an output controller (9, 10) with a drive means (14) and control means (16, 17) with a fixedly set fuel/air ratio. An oxygen detector (20) for keeping the level of residual oxygen in a waste gas passage (19) low influences a drive means (26) of an additional flap (27) by way of a controller (22). The control range of the additional flap (27) is limited, in dependence on the condition of the combustion air, by an additional controller (28, 30). When limit positions are reached, an alarm (44) is triggered and the air feed is increased again in order to prevent operation with a deficiency of air. That permits a basic adjustment with a low excess of air and correspondingly increased efficiency. IMAGE