| 摘要 |
<p>Apparatus provides an air/fuel mixture to a fully premixed burner and comprises means for providing fuel at a variable flow rate to the burner, means for supplying air at a variable flow rate to the fuel to form the mixture, and control means for controlling the fuel flow rate in dependence upon a heat output demand wherein, in use, the control means maintains the fuel flow rate at one of a number of differing predetermined values which are in the form of a geometric series where the ratio between successive values is constant.</p> |
