Heating and cooling system for service module

Claim 1

In a self contained service module of the type having at least a liquid coolant cooling system for an internal combustion engine and an air compressor; the improvement comprising heat exchange means including, a heat exchange housing, a low pressure air blower mounted in the housing, a fixed baffle in the housing dividing the air output from the blower into first and second independent air streams or flow paths, first and second indirect heat exchangers, means mounting the first indirect heat exchanger across the first air streams, means mounting the second indirect heat exchanger across the second air stream, conduit means connecting each indirect heat exchanger to a source of heated liquid from at least the cooling system for the internal combustion engine; independent first and second air outlets means one for each said first and second indirect heat exchangers; first duct means connecting the first outlet means to a zone to be ventilated; second duct means connecting the second outlet means from the second heat exchanger with an exhaust outlet; and a three way valve mounted in the conduit means connecting the indirect heat exchangers to the source of heated liquid, said three way valve operational to direct heated fluid from said source selectively to either the first or second heat exchanger or to both the first and second heat exchangers.