Precautions for Preventing Freezing in Water Chillers

Dear Valued Customers

With winter approaching, please ensure all refrigeration units are properly protected against freezing! When units are not in use during winter, drain all water from the condenser and evaporator in advance (evaporators in low-temperature units with outlet water temperatures below -10°C do not require draining).

When the unit is shut down during winter:

(1) Evaporator Drainage: A drain valve is located at the bottom of the evaporator. Ensure the evaporator inlet and outlet valves are closed before opening the drain valve to empty the water. For safety reasons, the drain valve may remain open.

(2) Condenser Drainage: After confirming the condenser inlet and outlet valves are closed, open the end caps at both ends of the condenser to drain water. For safety, the end caps at both ends of the condenser may remain open.

(3) Cooling Tower/Evaporative Cooler Drainage: First, drain the water from the sump basin. Then, remove the drain plug at the bottom of the water pump to drain the water. After drainage is complete, for safety, do not reinstall the pump drain plug temporarily to prevent the pump housing from freezing and cracking.

When continuing to operate the unit during winter:

(1) During short-term shutdowns, chilled water and cooling water should remain in circulation;

(2) For units equipped with cooling towers/evaporative coolers featuring anti-freeze heating functions, activate the anti-freeze and heating switches and conduct tests to ensure automatic heating capability.

Before restarting the unit after winter shutdown:

Since the system was drained during winter shutdown, do not start the unit before refilling it with water. Check whether the refrigerant pressure is normal. If any abnormalities are detected, immediately contact our after-sales personnel. Only proceed with operation after determining the cause of the malfunction.

Key Points:

(1) Two most common times for unit freezing damage:   Sudden temperature drops when the unit hasn't been drained or drained improperly.   During normal operation on workdays, but forgotten to drain before holidays.

(2) After freezing damage occurs: Beyond replacing frozen copper tubes (or the entire evaporator/condenser if multiple tubes are frozen), the system requires repeated thorough dewatering. During this process, the compressor and various valves may sustain damage or malfunction, necessitating replacement. Consequently, failure to drain the unit properly before winter can lead to significant waste of labor and resources.