Glycol Services for HVAC Systems
Glycol-based freeze protection is essential for any HVAC system that runs through unheated spaces, operates in cold weather, or needs to function at temperatures below freezing. In New York City — where buildings run chilled water systems year-round and outdoor air handlers are common — properly maintained glycol programs protect equipment from catastrophic freeze damage and keep systems running efficiently through the winter. Acqua Treat supplies, installs, and maintains glycol treatment programs for commercial buildings and facilities across all five boroughs.
When Does Your System Need Glycol?
Not every HVAC system needs glycol — but the ones that do can suffer serious damage without it. You need a glycol program if your building has:
Chilled water systems with outdoor or rooftop air-cooled chillers that operate in cold weather
Closed hydronic heating loops running through unheated mechanical rooms, crawl spaces, or exterior walls
Air handling units with chilled water coils in spaces that drop below freezing when the unit is off
Snow melt systems or exterior radiant heating piping
Heat pump systems with outdoor components
Any system where water flow stops during cold periods and the piping is exposed to freezing temperatures
If you are not sure whether your system needs glycol — or what concentration is appropriate — we can evaluate your system and make a recommendation based on your equipment layout, local temperature exposure, and operating schedule.
Our Glycol Services
We provide a full range of glycol services for commercial HVAC systems — from supply and new installation to ongoing maintenance and complete system changeouts.
Glycol Supply
We supply inhibited propylene glycol in the concentrations and volumes required for your system. We can supply premixed solutions at the required freeze-protection concentration, or supply glycol concentrate for dilution on site. Standard concentrations we supply:
30% propylene glycol — freeze protection to approximately -5°F (burst protection to lower temperatures)
35% propylene glycol — freeze protection to approximately -10°F, suitable for most NYC building applications
40% propylene glycol — freeze protection to approximately -15°F
New Glycol Installation
For new systems or systems converting from plain water to glycol, we handle the full installation process:
Initial system flush to remove water, sediment, oils, and construction debris
Pre-passivation chemical cleaning where required
Introduction of the glycol solution at the specified concentration
Concentration verification testing to confirm proper freeze protection level
Documentation of the glycol type, concentration, and volume installed
Glycol System Draining & Disposal
Glycol cannot simply be drained to the sewer — it requires proper handling and disposal in accordance with local environmental regulations. We manage the complete draining and disposal process for system changeouts, major repairs, or decommissioning. This includes:
Controlled system draining and glycol recovery
Coordination with licensed glycol disposal contractors
Documentation for project records
Glycol System Flushing & Changeout
Glycol does not last forever. Over time, the inhibitors in a glycol solution break down, the pH drops, and the fluid begins to corrode the system from the inside. Signs that your glycol needs to be changed:
Brown or dark-colored fluid in the system (indicates corrosion or glycol degradation)
pH below 7.0 (acidic glycol is actively corroding your piping)
Sludge, sediment, or particulate visible at drain points
Loss of freeze protection concentration due to dilution or leaks
Inhibitor depletion confirmed by water analysis
Our glycol changeout process includes draining and disposal of the degraded fluid, system flushing, chemical cleaning where needed, and refilling with fresh inhibited glycol at the correct concentration.
Glycol Concentration Testing & Monitoring
We provide glycol concentration testing as part of our ongoing water treatment service programs and as a standalone service. Testing confirms that your system maintains the freeze protection level you need and that inhibitor concentrations remain adequate. We test for:
Freeze protection concentration (glycol percentage)
pH (should remain between 7.0 and 9.5)
Inhibitor reserve levels
Presence of corrosion byproducts, sediment, or microbial contamination
Avoiding Costly Glycol Mistakes
Glycol systems fail for predictable reasons — most of which are entirely preventable. The most common problems we see in NYC buildings:
No testing program — glycol pH drops over time and nobody checks until corrosion causes a pipe failure or pump failure
Wrong concentration — too little glycol and the system freezes; too much and heat transfer efficiency drops, putting strain on the pump
Mixing glycol brands or types — different inhibitor chemistries can react, forming sludge that clogs strainers and heat exchangers
Topping off with plain water after leaks — over time this dilutes the glycol to below the required freeze-protection concentration
Using automotive antifreeze — automotive glycols contain silicate-based inhibitors that are not compatible with HVAC systems and will damage pumps and heat exchangers
If your system has any of these issues, contact us. Early intervention — a water analysis and a glycol changeout if needed — is far less expensive than dealing with a frozen coil, a burst pipe, or a failed heat exchanger in January.
We serve buildings throughout Manhattan, Brooklyn, Queens, the Bronx, Staten Island, and surrounding areas. Contact us for a free assessment of your glycol system or a quote for supply and installation.