BOILER

摘要

Disclosed is a boiler that controls the burning capacity in multiple combustion stages, which boiler makes it possible to cancel shifting between combustion stages, while also preventing problems that accompany such cancellation. The disclosed boiler is equipped with an air supply device that enables changing of the combustion air supply quantity, a fuel supply device that enables changing of the fuel supply quantity, and a control means that controls the air supply device and fuel supply device so that the quantities supplied correspond to various combustion stages to realize multiple combustion stages. When a request is received to cancel shifting during the shift from a specified combustion stage to another combustion stage, the control means controls the air supply device and fuel supply device to return to the specified combustion stage, and controls so that control to shift to the other combustion stage is not carried out until a re-cancel prohibition period has elapsed.