(under subclass 412) Water heaters for keeping water in a fire engine boiler hot when the fire engine is in the engine house and the firebox is not in use, which consist of a stationary water heater located in the engine house, adapted to be coupled to the fire engine boiler to establish a water circulation.
SEE OR SEARCH CLASS
237, Heating Systems,
12.2, for combinations of this heating device with the heating system of the engine house.
