Differences between chillers and heat pumps

The water chiller, namely the refrigerator, is mainly used to cool the equipment. With the compressor as the core, the heat can be transferred from the low temperature evaporator end to the high temperature condenser end by reasonably matching the evaporator, condenser and corresponding throttling capillary tubes, so as to effectively cool the evaporator end. The heat pump is a unit that can produce both cold water and hot water. With switching function, it can be switched to water chiller in summer and hot water unit in winter to produce hot water.

The difference between water chillers and heat pumps can be summarized as follows: different components, different structures and different purposes.

The water chiller only has a single refrigeration and cooling function. It takes the environment as a high temperature heat source. The main components of its system are compressor, condenser, throttling component and evaporator. The refrigerant flows unidirectionally in the evaporator and condenser. The heat exchange area of the evaporator and condenser of the water chiller can be appropriately reduced, and the compressor capacity can also be appropriately selected to be smaller. The balance can be achieved by increasing the air volume of the condensing fan and the evaporating fan.

In order to switch the cooling and heating mode of the heat pump unit, in addition to the compressor, condenser, throttling component and evaporator, there is also a very important component in the system pipeline - four-way reversing valve. The system implements the switching of the four-way reversing valve to achieve the conversion of the cooling and heating mode of the heat pump unit. However, in a short time when the four-way reversing valve of the heat pump unit is switched, more liquid refrigerant will flow to the compressor. In order not to cause the compressor liquid hammer and prevent the liquid refrigerant from returning directly to the compressor, a gas-liquid separator with appropriate size needs to be added on the compressor suction line. The refrigerant flow required for unit heating execution is less than that required for refrigeration execution. Excess refrigerant needs to be stored in a special liquid storage tank. A special liquid storage tank is set in the heat pump unit system.

When the energy interaction between the water chiller or heat pump and the surrounding environment is to absorb heat from the low temperature heat source, and then release heat to the high temperature heat source, its purpose is to obtain the high temperature, that is, to generate heat, that is, to release heat to the high temperature part, that is, the heat pump; If the purpose is to obtain low temperature, namely refrigeration, that is, to absorb heat from a low temperature heat source, it is a refrigeration chiller.

Generally, the heat pump water heater uses the environment as a low temperature heat source, while the water chiller uses the environment as a high temperature heat source. Heat pump unit and water chiller are basically the same in principle. Heat pump is a refrigeration system that uses heat from condenser or other parts to provide heat. In principle, any cycle that can be used as a chiller can be used as a heat pump cycle, and any analysis method that can be used for a chiller can be used to analyze a heat pump.