Do I Need To Treat My Closed Loop System for Organic Growth?

Geothermal Installation

Geothermal and chilled water closed loop systems need to be treated for organic growth. Here we offer tips on cleaning and treating your system, and discuss what happens if you don’t treat.

Initial Cleaning Post-Installation:

Closed loop systems should always be properly flushed and cleaned after the initial installation and before the first fill. Oil, debris, and slag left over from welding and construction of the system could easily be present and will circulate through the system after the initial fill if it is not cleaned out properly. When water or heat transfer fluids begin circulating and are then continuously in contact with the debris and contaminants, they begin to take on a microbiological character. Dissolved microbes in the water can turn into the start of corrosion and organic growth in the system.

Ongoing Treatment & Maintenance:

There are many ways leaks may develop in your system. They may develop unnoticed, or after a repair (i.e. digging up a geothermal loop). If dirt or air or any type of bacteria or contamination is allowed into your system through a leak and is not addressed, this is essentially asking for problems. We frequently receive samples of heat transfer fluids for testing that contain some kind of dirt, debris, or microbiological growth in them, as it is a common problem.


Tips on Cleaning and Treating a Closed Loop System to Prevent Organic Growth

After installation is complete, the system should be properly cleaned using either a sodium hypochlorite (bleach) solution or a closed loop system cleaner such as GlycoClean. This will ensure all contaminants are out of the loop prior to the initial fill. A good inhibition package such as GlycoHib I-50 should then be added to the water / glycol solution used in the initial fill. This will circulate in the system as long as the useful lifespan of the product has not been used up and will keep bacteria from growing that may enter the system through potential hidden leaks. In addition to killing off bacteria, it will also create a film on the inside of the pipes to ensure that nothing from the material in the pipe will break down and contaminate the system.

Annually, the fluid in your system should be analyzed, and if the fluid has been ‘spent’ (the useful lifespan used up), the fluid will need to be replaced.


What Happens If I Don’t Treat My System?

If a system is not properly maintained, it is highly likely that problems will begin to multiply over time. Organic growth and corrosion will eventually lead to system failure, pump failure, and/or decreased efficiency of the equipment as the heat transfer-ability of the fluid is lessened through contamination in the system.

With questions about treating your closed loop geothermal or chilled water system for organic growth, or getting your annual fluids analysis, contact us.