Canadian Consulting Engineer
Caution for geo-exchange installationsBuildings Building Mechanical & Electrical (HVAC) Systems
The Heating, Refrigerating and Air-Conditioning Institute of Canada (HRAI) has issued a hazard alert acro...
The Heating, Refrigerating and Air-Conditioning Institute of Canada (HRAI) has issued a hazard alert across the country, following notification about safety incidents with ethanol in geothermal (geo-exchange) pump installations.
The Ontario Ministry of Labour notified HRAI about the incidents and have recommended safety measures.
A growing number of geothermal systems are using an ethanol-water mixture as a more environmentally friendly alternative to glycol in the heat exchange fluid.
But In one reported case, ethanol and water were being mixed in a home basement. The mixture spilled onto the floor and the vapours were ignited and resulted in a fire.
HRAI points out that an ethanol-water mixture as low as 20% in the total system volume would be classified in Class IC flammable liquids by the NFPA 30 Flammable and Combustible Liquids Code.
One of several safety recommendations from the Ontario Ministry is that all sources of ignition must be at least 3 metres from the ethanol or ethanol-water mixture, including flush carts.