How To Add Glycol To A Closed Loop System

How to Add Glycol to a Closed Loop System

Adding glycol to a closed loop system, such as a radiant floor heating system or industrial chiller, is crucial for freeze protection and improved heat transfer. However, doing it incorrectly can lead to system damage. This guide provides a step-by-step approach to ensure a safe and effective glycol addition.

Understanding Glycol Types and Concentrations

Before you begin, it's essential to understand the type of glycol and the appropriate concentration for your specific system. The two most common types are propylene glycol (non-toxic) and ethylene glycol (toxic). Ethylene glycol should only be used in closed systems where leakage is extremely unlikely. The correct concentration depends on the lowest anticipated temperature your system will experience. Consult the manufacturer's specifications for your system and the glycol product for precise recommendations. Generally, higher concentrations provide better freeze protection but can also impact pump efficiency and system longevity.

Choosing the Right Glycol

• Propylene Glycol: The safer option, ideal for residential and applications where leakage is possible.
• Ethylene Glycol: Offers slightly better freeze protection but is highly toxic, requiring extreme caution.

Determining the Correct Concentration

The optimal glycol concentration is crucial. Too little, and you risk freezing; too much, and you risk damaging system components. Always refer to the manufacturer's guidelines for your specific system and glycol.

Step-by-Step Guide to Adding Glycol

Safety First! Always wear appropriate safety gear, including gloves and eye protection, when handling glycol. Ensure adequate ventilation.

1. System Shutdown: Completely shut down your closed loop system. This means turning off the power to the pump and any other related equipment.

2. Locate the Expansion Tank: Identify the expansion tank or pressure vessel. This is typically the highest point in the system and often contains air.

3. Drain a Portion of the Fluid (Optional): If you need to reduce the existing fluid concentration or the system is significantly overfilled, carefully drain a portion of the fluid from the expansion tank or a convenient drain valve.

4. Add Glycol Solution Slowly: Gradually add the pre-mixed glycol solution to the expansion tank. Avoid rapid pouring to prevent foaming and ensure proper mixing. Never add glycol directly to the pump or other components.

5. Mix Thoroughly: After adding the glycol, carefully run the system pump for a few minutes to thoroughly mix the solution. Allow the system to circulate for a period of time to ensure uniform distribution of the glycol. Refer to your equipment's documentation.

6. Check and Adjust: After mixing, check the pressure gauge to ensure it is within the normal operating range. Add more fluid or air as necessary to maintain the correct system pressure. Check for leaks.

7. System Startup: Once the glycol is properly mixed and the pressure is correct, restart your closed loop system. Monitor the system's performance closely to ensure everything is working correctly.

Regular Maintenance and Monitoring

Regularly check the glycol concentration using a refractometer. This ensures optimal freeze protection and system performance. Over time, the concentration can decrease due to evaporation or leaks. Top off with the correct glycol solution as needed.

Conclusion

Adding glycol to a closed loop system is straightforward when you follow the correct procedures. Prioritizing safety, understanding your system's requirements, and performing regular maintenance will ensure your system's longevity and efficiency. Remember to always refer to your system’s manufacturer's instructions for specific details and recommendations.