More commonly referred to as antifreeze, glycol protects hydronic heating and cooling systems — specifically boilers and chillers — from freezing in cold climates. It also improves the properties of heat transfer fluids by:
- Raising the boiling point
- Lowering the freezing and burst points
- Reducing system component corrosion
Heat transfer fluid can freeze in cold temperatures due to insufficient glycol concentrations. Depleted glycol also accelerates corrosion. Both conditions can cause significant damage to HVAC systems.
Glycol types
There are three glycol types in use:
- Propylene – a non-toxic material used in heating and chiller systems
- Food grade – available for use for heating and cooling in food production
- Ethylene – a toxic material used in automotive and stationary generator systems and some industrial applications
Geothermal systems in northern climates may use a combination of propylene glycol and ethanol to prevent freezing at very low temperatures.
Glycol degrades over time from exhaustion of corrosion inhibitors, overheating or particulate accumulation in the system. Propylene necessitates special handling and disposal methods while ethylene and propylene glycol-ethanol mixtures require handing as hazardous wastes.
Read about Glycol Concentration Restoration in Intricate Chiller System Project.
Alliance Environmental Group (AEG), an F.W. Webb company, can handle all your glycol needs from removal to replacement including:
- Drain spent glycol from HVAC systems, including air handlers, piping, chiller units, or boilers
- Flush the system with a cleaning solution and water to remove residual spent glycol, scale, and corrosion products
- Ship replacement glycol to jobsite
- Replenish the system with proper concentration of fresh glycol — with or without corrosion inhibitors
- Transport used glycol and flush water to a licensed disposal or recycling facility
AEG employs a team of OSHA-trained scientists, engineers, and experienced technicians. Our proven track record of success across the Northeast allows us to help you select all the right products and services for your glycol-based heat transfer fluid maintenance needs.
