The Enviro-Guard pressure relief valve and rupture disk assembly is designed to provide refrigerant loss protection due to an overpressure situation. The assembly comes as a complete unit that mounts to the vent line on the chiller outlet and can be used with any low-pressure chiller using R-123, R-113, or R-11, says the manufacturer. Enviro-Guard uses a nonfragmenting rupture disk between the vent piping and the relief valve. If an overpressure situation occurs, the rupture disk will burst, but will not release the refrigerant into the atmosphere, but will instead provide a level of protection and reset within 10% of the rated pressure setting, says the manufacturer.

TVS Products, attn: Jim Cain or Barb Barca, 1300 East Memphis, P.O. Box 1957, Broken Arrow, OK 74013; 800-324-7035; 918-251-6426 (fax); (e-mail); (website).

eProduct #183