Glycols age slowly, with some percentage of the molecules “cleaving” into glycolic and formic acids. As with most chemical reactions, heat expedites this process. If there are insufficient chemical inhibitors present in the HTF, this process can accelerate, creating a corrosive liquid.

We’ve seen pipes, zone valves and pump casings severely damaged by old, foul, neglected HTF’s. Annual testing of your HTF for pH, inhibitors and clarity is the best way to prevent expensive, unseen damage to your HVAC system.