Abstract: A multi-pass parallel tube heat exchanger is disclosed. The multi-pass parallel tubes heat exchanger provides a compact, light and inexpensive heat exchanger that may be oriented in any direction. These features and others make the disclosed exchanger ideal for use in a restricted area such as that available when providing localized cooling systems. This design is more efficient than the prior art and allows for a versatile operation with multiple circuiting options for the flow path and enhanced performance with multiple fluid and heat transfer operations.