How To Correctly Select And Use Antifreeze For Your Chiller In Winter ?

Antifreeze: An Indispensable Winter Guardian

When the minimum ambient temperature is ≤0℃, and the purified water in the system is not drained after equipment shutdown, antifreeze must be added to the entire system. The antifreeze should be an ethylene glycol-based product, and the ethylene glycol volume concentration must not exceed 60%.

How to Correctly Select and Use Antifreeze?

Important Note: Industrial chiller systems must uniformly use ethylene glycol-based antifreeze; ethanol-based antifreeze is strictly prohibited. Ethanol-based products are highly volatile, have poor freezing point control stability, and easily lead to system vapor lock and aging and damage to seals.

Antifreeze usage guidelines are as follows:
Recommended mixing ratios:
6:4 (60% antifreeze, 40% purified water) -30°C to -40°C
5:5 (50% antifreeze, 50% purified water) -20°C to -30°C
4:6 (40% antifreeze, 60% purified water) -10°C to -20°C
3:7 (30% antifreeze, 70% purified water) +10°C to -10°C

While ensuring the freezing point meets requirements, the concentration should be minimized to reduce the risk of corrosion to pipelines.

Usage period: Antifreeze should not be used for extended periods. When the ambient temperature remains above 5°C, the system should be drained promptly, and the system should be flushed multiple times with purified or distilled water before refilling with purified water as the cooling medium.

Mixing is strictly prohibited: Different brands or models of antifreeze may have different compositions; mixing them may cause chemical reactions. Please use the same product throughout the process, and thoroughly clean the system before replacement.

The steps for adding antifreeze are as follows:

1. Close the drain port to prevent the added coolant from flowing out;

2. Based on the lowest ambient temperature, the appropriate ethylene glycol mixed coolant should be selected according to the ethylene glycol freezing point table and the total volume of coolant required by the chiller;

3. Add the mixed coolant to the chiller tank through the fill port until the coolant level reaches the green area of ​​the display. Then, turn on the water pump to circulate the entire chilled water system several times.

Antifreeze is a crucial line of defense for production continuity.

In precision manufacturing, temperature is not only related to accuracy but also directly linked to safety and stability. A single equipment downtime due to freezing not only results in repair costs but also disrupts the entire production line and delays orders. Preparing for chiller antifreeze in advance is essentially an important investment in production continuity. If you have any questions about antifreeze selection or actual operation, Hanli Refrigeration's after-sales service team is always ready to provide you with professional technical guidance to help your equipment  worry-free production operation in severe cold weather.