- 1. Do not use antifreeze intended for cars
- 2. Use the correct Glycol for your application and product
- 3. Only use inhibited glycol in your chiller
- 4. Don’t mix different types of glycol
- 5. Check environmental regulations surrounding your equipment
- 6. Use the correct dosage of Glycol
- 7. Mixing Glycol with the right water
- 8. Chiller & system hygiene maintenance
GLYCOL – WHY DO I NEED TO USE IT IN MY CHILLER IN THE FIRST PLACE?
If your cooling system operates at below 6°C, or is based in a location where the ambient temperature can approach 0°C, Glycol provides protection against the water in the pipework of the system freezing. This will cause the unit to operate inefficiently and could cause the pipework to burst damaging your equipment and stopping your process in its tracks.
If you’re completely new to the application of Glycol and need a reference for the future, you will find below a few vital points to keep in mind when selecting the right Glycol for your unit.
1. Do not use antifreeze intended for cars
Automotive Antifreeze is formulated specifically for use in automotive engines which operate at much higher temperatures. It is therefore unable to maintain the levels of heat transfer required for a chiller.
Automotive Glycol can also contain other non-glycol chemicals, including alcohol or glycerin. These differences can lead to clogging in your system’s pipework, causing your unit to under perform and fail over time. Automotive Glycol might be more readily available, but you should always buy Glycol from a specialist provider.
2. Use the correct Glycol for your application and product
You should consider toxicity as a major factor when purchasing Glycol, because depending on what product you produce or service you provide, the Glycol will need to meet minimum toxicity requirements. If you’re working in an industry that does create products that are consumed, an ethylene-based Glycol, such as Flowcool IG will likely be suitable.
If you’re in the Food and Beverage industry or an industry where the user will come into frequent contact with the system, it’s a legal requirement that the Glycol used is food safe (propylene based) to ensure that no risk is posed to your customers.
Check with your supplier to ensure that the Glycol they are providing has been tested by a reputable body, such as the National Sanitary Foundation, to ensure that it is compliant and safe.
3. Only use inhibited Glycol in your chiller
Glycol, due to its chemical composition is corrosive to metal in its uninhibited form, meaning it will cause the internal pipework in your chiller to corrode, scale and rust – sometimes too quickly to be noticed before there’s a problem. By using inhibited Glycol, (which contains inhibitors that bind to the internal pipework of your system), a thin molecular layer will be created that protects your system but doesn’t effect your system’s efficiency.
4. Don’t mix different types of glycol
Because of the chemical differences and variances in formula between brands, it is important that you not only use the correct type of Glycol, but also the same brand. Failure to maintain consistency can cause the inhibitors in the formula to stop working. This will clog up your pipework because of incompatibility.
5. Check environmental regulations surrounding your equipment
Every aspect of manufacturing is under scrutiny by environmental agencies. Chiller water systems are no different due to the danger they pose to the environment. Much like refrigerants, Glycol and its environmental impact is under constant scrutiny. Ensure that you have an environmentally responsible plan for storage and disposal of Glycol or you could face a fine.
6. Use the correct dosage of Glycol
It is important to ensure that you use the correct concentration of Glycol for your unit. Too little can lead to bacteria growth or freezing in the pipes – which will cause damage to the internal pipework of your system. Too much Glycol can lead to the fluid in your unit becoming thicker than the internal pump can handle. This can damage your equipment and lower its lifecycle. Concentrations over a certain threshold can even cause the freezing temperature of the liquid to rise. This can reverse the benefit of using Glycol in the first place.
7. Mixing Glycol with the right water
Many businesses use water that comes directly from the tap or ground mains. These can contain deposits – that are invisible to the human eye – or additives such as fluoride that can interact poorly with the Glycol and internal systems of the unit. This can shorten their lifespan and increase the cost of servicing the unit.
Because of the above issues, it’s recommended that you use “pure” water that has been distilled, demineralized, deionized or reverse osmosised. This is a process that removes the salt in the water of your system and will reduce the unpredictability associated with tap water.
8. Chiller & system hygiene maintenance
The chilled water system must be flushed, cleaned and sanitised prior to adding a new water/glycol solution.
The water/glycol solution must be regularly sampled and tested to ensure there are no underlying or progressive contamination and/or corrosion issues arising.