Do you have a new HVAC service contract and the glycol smells burnt and is brown? Send a sample to our glycol lab! Houghton Chemical provides complementary glycol testing to our customers. Our glycol analysis will determine if your system contains ethylene glycol, propylene glycol, or a glycol mix. We will also determine, glycol concentration, glycol pH, reserve alkalinity, and offer complete recommendations. Let us know you know your glycol!