1) When the ambient temperature drops below 3°C, equipment should be protected from freezing.
2) For equipment not in use during the winter, drain all water from the condenser and evaporator, keeping the drain valves open at all times to prevent water accumulation and damage to the heat exchange tubes.
3) For computer rooms equipped with constant temperature equipment, maintain a minimum temperature of no less than 5°C year-round.
4) Alternatively, add an appropriately concentrated antifreeze solution (ethylene glycol) to the piping system.