Abstract: An inducer (40) for causing a flow of combustion air into and gases of combustion through and out of a furnace (10) of the condensing type. The inducer is intended for use, without modification of its design or size, in a series of furnaces of the same basic design but having different heating capacities and therefore different requirements for flow through the induction flow path. The furnace design is such that a given furnace is capable of operation so as to provide a flow of air to be heated that is either up, down or horizontal with only minor field modification on installation. The inducer has two discharges (43), only one of which is used in a given installation. The other discharge is blocked with a plug (61) of special configuration that can vary the output of the inducer to ensure optimum flow of combustion air into and gases of combustion through and out of the furnace.

Abstract: Suction gas is used to cool the motor of a low-side hermetic compressor. The suction flow is divided. A small amount of the suction flow, e.g. 15%, is diverted to cool the motor and is recombined, via aspiration, with the main flow which is supplied directly to the inlet of the running gear of the compressor.