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<\/p>\nIn addition to heating a property or building, an air-to-water heat pump can also provide cooling. In this mode, the thermodynamic cycle is reversed, and the building is cooled via underfloor heating or another emission system. This cooling process is made possible by a four-way valve within the heat pump. This valve alters the flow direction of the refrigerant. In this article, we explain exactly how the four-way valve in a heat pump operates.<\/p>\n
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The four-way valve allows a heat pump to provide both heating and cooling. This mechanism changes the direction in which the refrigerant flows through the device, effectively reversing the functions of the heat exchangers: the finned tube exchanger becomes the condenser, and the plate heat exchanger becomes the evaporator. Inside the four-way valve is a sliding mechanism known as the actuator. An electromagnetic force triggers this component to switch to the desired position. This shift in the actuator changes the refrigerant's flow path, allowing the heating water in the building to be either cooled or heated, depending on the requirements.<\/p>\n
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A heat pump operates on a closed cycle consisting of four main components: an evaporator, a compressor, a condenser, and an expansion valve.\n\nDuring heating: The evaporator (finned tube exchanger) extracts heat from the outside air. The refrigerant evaporates, is pressurized by the compressor (which further increases the temperature), and then releases heat to the building's water circuit via the condenser (plate heat exchanger).<\/p>\n
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During cooling: This is where the four-way valve comes into play. It reverses the flow direction of the refrigerant, swapping the roles of the heat exchangers. The finned tube exchanger now acts as the condenser, and the plate heat exchanger acts as the evaporator.<\/p>\n
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The cooling process step-by-step:<\/strong><\/p>\n <\/p>\n This process creates chilled water in the building's circuit, which radiates \"cold\" via underfloor heating, climate ceilings, or other emission systems.<\/p>\n <\/p>\n <\/p>\n When temperatures drop in winter, frost and ice can build up on the finned tube exchanger. In this case, the heat pump automatically melts the ice by running a defrost program. The four-way valve switches to the \"cooling\" position, causing the finned tube exchanger to heat up due to the reversed cycle. Once the ice has melted, the four-way valve switches back, restoring the original flow direction to resume heating the building.<\/p>\n <\/p>\n <\/p>\n <\/p>\n Our heat pumps utilize the four-way valve to provide both heating and cooling. We even offer 4-pipe systems that can heat and cool simultaneously. This is particularly beneficial for environments like hospitals, where operating rooms with sensitive equipment may require cooling while public areas need to be heated at the same time.<\/p>\n <\/p>\n Interested in seeing our technology in action? Please feel free to contact us or visit our factory. We have a working heat pump system on-site for you to inspect. We look forward to welcoming you.<\/p>\n <\/p>\n\n
The four-way valve during the defrost cycle<\/h2>\n
![\"Werking](\"https:\/\/www.ecohs.nl\/wp-content\/uploads\/2026\/03\/Werking-vierwegklep-bij-defrosten-warmtepomp.png\")
<\/p>\nWant to learn more about our heat pumps?<\/h2>\n
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