Valves are required when the chiller needs to be shut down or turned on. The main function of valves is to control the flow and direction of refrigerant. Valves should be installed in places that are easy to disassemble and maintain. When installing various valves, attention must be paid to the flow direction of refrigerant and they cannot be installed in reverse. The thermal expansion valve in the chiller must also be installed horizontally, and attention should be paid to the inlet and outlet connections of the valve. Usually, there is a filter screen at the inlet end of the valve. If the thermal expansion valve is well controlled, the position of the temperature sensing bulb is very important.

The temperature sensor should be firmly fixed on the clean suction pipe to ensure good contact between the temperature sensor and the suction pipe. The external balance pipe of the external balance thermal expansion valve should be installed at the lower part of the binding point of the return pipe temperature sensing bulb, with a distance of 150-200mm from the binding point of the temperature sensing bulb. The temperature sensing bulb should be tied to the horizontal pipe section, and the external balance pipe should be connected from the top of the horizontal pipe section of the return pipe.

When installing a flange type valve on a chiller, the flange plate and valve flange must be padded with high-pressure asbestos board, and the thickness of the high-pressure asbestos board should be determined according to the depth of the flange groove on the valve. When the valve is large and the groove is deep, a thicker asbestos board should be used to avoid gaps between their concave and convex interfaces that may result in poor sealing. When assembling flange valves, it is important to ensure that all bolts are evenly stressed, otherwise the concave convex interface may be prone to compression deviation. When installing a shut-off valve on a chiller, the working fluid should flow from the bottom of the valve to the top. When installing on a horizontal pipeline, the valve stem should be vertically upward or tilted at a certain angle, and it is forbidden for the valve stem to face downwards. If the valve position is difficult to access or high, for ease of operation, the valve stem can be installed horizontally.

When installing a check valve on a chiller, ensure that the valve core can automatically open. For lift check valves, it should be ensured that the centerline of the valve core is perpendicular to the horizontal plane. For rotary check valves, the rotation of the valve core plate should be ensured, and the valve core plate must be installed horizontally. The safety valve of the chiller should be directly installed on the shut-off valve at the outlet of the equipment, and the arrow on the valve body should be consistent with the direction of the working fluid flow. The solenoid valve of the chiller must be installed horizontally at the outlet of the equipment, and must be installed in the position specified in the drawing. If the solenoid valve is installed in front of the throttle valve, a minimum distance of 300mm should be maintained between the two.