York Switch, Liquid Level 025-43324-000

025-43324-000 is the original factory liquid level switch (Switch, Liquid Level) for the cooling units of York (a brand under Johnson Controls). It is a component for monitoring and protecting the refrigerant level. The specific model numbers within this range in York's accessory system have been confirmed as 025-43324-101 (SWITCH LIQUID LEVEL CORSAIR, marked for Corsair series units) and 025-43324-001 (listed by the accessory manufacturer as York Chiller Liquid Level Sensor, with a brass or stainless steel housing, 24V AC/DC power supply, measurement range of 0–100% liquid level, pressure resistance up to 300 psi, output of 4–20 mA or relay signal, response time of 1–2 seconds, protection level of IP65/IP67). The original part name of 025-43324-000 is not publicly disclosed. The suffixes -000/-001/-101 usually correspond to different unit versions or installation forms and cannot be interchanged merely based on appearance.
This component is installed at the liquid level observation position of the evaporator or condenser to monitor the level of the refrigerant in real time and send signals to the control system: when the level is too low, it alerts of insufficient refrigerant and prevents loss of heat exchange area of the evaporator and suction air void of the oil pump; when the level is too high, it prevents liquid from entering the compressor and causing liquid impact. York's similar liquid level sensors also include 025-46044-006 (R-134a liquid level sensor), belonging to different models and refrigerants. Failure of the liquid level switch can lead to false liquid level readings, incorrect protection of the unit by the control system or loss of low liquid level protection. During maintenance, power should be disconnected before checking the connectors and signal output, and comparing with the standard values given in the service manual. Replacement must check the model, serial number and refrigerant type of the unit, and it is recommended to be operated by qualified refrigeration maintenance personnel.