Refrigerant recovery on rooftop.Legislative requirements and the rising cost of refrigerants—both financial and environmental—call for the chilling system industry to perform safe and efficient methods of refrigerant recovery. In this article, we look at the most common refrigerant recovery methods used and why they are necessary. We also provide you with useful tips for servicing your chilling system in an efficient and environmentally friendly way.
Why Recover, Recycle, and Reclaim Industrial Refrigerants
Ever since the Clean Air Act of 1990 and the Montreal Protocol treaty the industrial refrigeration industry has been required to recover, recycle, and reclaim refrigerants or face hefty government fines. Why? Because whether in gas or liquid form, synthetic refrigerants can have a damaging impact on the environment.
When chillers and refrigeration systems are being serviced or replaced, the release of synthetic refrigerants into the atmosphere can have a harmful effect on the ozone layer. Disposing of liquid refrigerant at the disposal facility alters the chemical makeup of the soil. Taking measures to limit the use of refrigerants helps to preserve our environment and keep our communities safe.
Reclaiming and reusing refrigerants helps save money, too. Because of the environmental factors above it is becoming increasingly more expensive to replace and to dispose of refrigerants. Chilling system operators can improve their bottom line by ensuring that best practices for refrigerant recovery are observed when servicing or replacing their equipment.
Methods of Refrigerant Recovery
There are (3) basic methods for reclaiming and reusing refrigerants in chilling systems:
- Liquid Refrigerant Recovery – Able to transfer refrigerant while it is still in the liquid state. This method is especially good for transferring refrigerant from one container to another.
- Vapor Refrigerant Recovery – The refrigerant is removed in a vapor state. The vapor is then condensed into a liquid form by the recovery unit and finally transferred to the recovery cylinder.
- Push-Pull Refrigerant Recovery – This method is used for transferring large volumes of liquid refrigerant—usually greater than 20 pounds of refrigerant. The recovery unit “Pulls” vapor from the recovery cylinder and produces high-pressure discharge gas that “Pushes” liquid out of the system and back into the recovery cylinder.
Best Practices for Refrigerant Storage Cylinders
Regardless of which recovery method you choose, having the appropriate size and quantity of storage cylinders on site during the process is key.
Refrigerant types should never be mixed and/or stored together. Combining R22, R134, R410 or other refrigerants can yield unexpected results. (If you are unsure of the purity of your refrigerant submit a sample to an AHRI certified lab for most accurate results.)
Storage tanks must never be filled beyond 80% capacity and that the weight capacity for each depends on the type of refrigerant used. Here is a quick reference chart to show the maximum amount of refrigerant that can be stored in a 30 lb or 50 lb cylinder tank depending on the refrigerant type.
10 Important Do’s and Don’ts for Recovering Refrigerants
- Do follow safety precautions: always wear goggles and gloves when servicing chilling equipment and reclaiming refrigerants.
- Don’t guess at the quantity or type of refrigerant used.
- Do be careful when connecting gauges. The low-side gauge can be damaged by over pressuring it with high-side pressure liquid or vapor.
- Don’t assume you know how the unit works. Be sure to read the operating instructions for the specific recovery machine you are using as each unit differs by manufacturer.
- Do use a machine with a high vapor recovery rate. Vapor recovery can account for up to 80% of the process.
- Don’t use long hoses. The shorter and wider the hose, the faster the refrigerant will be removed.
- Do get the liquid out first. After this has been completed work to eliminate the vapor.
- Don’t expose your recovery machine to harmful elements. Always use an inline filter at the inlet port to keep out slivers and avoid damaging it internally.
- Do purge your recovery equipment between jobs.
- Don’t forget to check the recovery tank certification. It must be recertified every 5 years.
If you would like to learn about environmentally friendly refrigerant solutions for chillers read this article on how Natural Refrigerants are Changing the World.
To request a refrigeration technician to service your chilling system, contact us.