The Enviro-Guard pressure relief valve and rupture disk assembly from TVS Products (Broken Arrow, OK) 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 is suitable for any low pressure chiller using HCFC-123, CFC-113, or CFC-11. Available sizes include 2x2, 2x3, 2x4, 3x3, and 4x4.