A:The unit will count the air return overheat state due to the air return temperature, then send signal to the control module. The control module will send directive to the centrifugal compressor and the electronic expansion valve. So the centrifugal compressor will adjust the revolution rate, and the electronic expansion valve will adjust the flowing volume. The load control can be adjusted at random, to save energy efficiently.

A:The compressor takes in low-pressure superheat refrigerating gas from the dry-type evaporator andcompresses it into high-pressure, high-temperature steam-gas. The steam-gas discharges heat to the ambient environment when going through the condenser and is condensed into saturated or super-cool refrigerating liquid, which flow is regulated and pressure reduced through expansion valve. Then, the liquid flows into the dry-type evaporator, where it absorbs heat from cold water, gasifies and is again taken in by the compressor to start a new cycle. Thus, the cold water passing the dry-type evaporator is cooled down and flows into the air-conditioning area.

In heat pump cycle, the direction of refrigerant flow is switched over by means of four-way valve. After being compressed by the compressor, the high-pressure, high-temperature refrigerating gas is directly discharged intothe shell and tube heat exchanger (dry-type evaporator) and heat is released to cold water in this process torealize heating. The condensed refrigerant flows through expansion valve, where its flow is regulated and pressure reduced and then evaporates in the air-cool condenser by absorbing ambient heat. The gas is then taken in by the compressor to start a new cycle.