Correcting Glycol Concentration (Balancing HVAC System Concentration)

An important part of system maintenance is regularly testing your heat transfer fluids to ensure that corrosion and freeze protection are present in the correct concentrations. If after testing, you learn that the glycol concentration is not high enough to provide freeze protection or burst protection to your lowest anticipated temperature (the antifreeze freezing point), it is necessary to correct the glycol concentration through glycol addition. Correcting the glycol concentration in your system can help to protect against cold weather or to replace fluid lost through leakage.

If you find yourself asking how much glycol is needed to correct the glycol to water mix ratio in your hydronic heating or cooling system, we have created a helpful tool to do the calculations for you.

Increasing the glycol concentration in your system is easy with our Glycol Concentration Correction Calculator, including step-by-step instructions.

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Instructions for Increasing the Concentration of Glycol in Your System:

Step 1: Using the above Concentration Correction Calculator, determine the total volume (in gallons) of 100% concentrated glycol required to increase your system's concentration to the desired percentage.

Step 2: Use the total volume identified from Step One and our Container Quantity Calculator to determine the container sizes and quantities of 100% concentrated glycol to you will need purchase to make the correction. 

Remember, you will need to drain out some of your current fluid before adding in the 100% concentrated glycol. The total volume (in gallons) you are adding to the system is same amount you will need to drain. For example, if you will be adding 375 gallons of 100% concentrated glycol to the system, you must first drain out 375 gallons of your current heat transfer fluid. 

If you need to purchase empty containers to pump your used fluids into, you can use the Container Quantity Calculator to determine these container sizes and quantities as well.

Step 3: Purchase your glycol and empty containers for draining (if needed). Begin Step 4 once your order has arrived. 

Step 4: Drain out the total volume (in gallons) of your current heat transfer fluid that you will be replacing with the purchased 100% concentrated fluid. For example, if you will be adding 375 gallons of 100% concentrated glycol to the system, you must first drain out 375 gallons of your current heat transfer fluid. 

Be sure to dispose of your used fluids properly. For more details, you can find our Disposal Instructions here

Step 5: Add the total volume (in gallons) of 100% concentrated glycol purchased into your system. 

Step 6: Circulate for at least 24 hours to ensure complete mixing. Check your system's concentration with a refractometer or preferred testing method to confirm that the correct concentration was achieved.