Heat transfer circuit with flow dependent heat exchanger

A heat transfer circuit operable in at least a first mode and a second mode, the heat transfer circuit comprising:

• a compressor to compress a working fluid;
• an expander to expand the working fluid;
• a first heat exchanger to exchange heat between the working fluid and a first process fluid, the first heat exchanger including a plurality of heat exchange coils, the working fluid flowing through the plurality of heat exchange coils, the first process fluid flowing through the plurality of heat exchange coils in parallel;
• a second heat exchanger to exchange heat between the working fluid and a second process fluid,
• a reversing valve configured to change a flow direction of the working fluid through the first heat exchanger;
• and
• a plurality of valves configured to direct the working fluid through the plurality of heat exchange coils of the first heat exchanger based on the flow direction of the working fluid through the first heat exchanger,
• wherein the working fluid flows through the plurality of heat exchange coils in series when the flow direction is a first direction, and the working fluid flows through the plurality of heat exchange coils in parallel when the flow direction is a second direction.