Products From NFPA World Safety Expo"
Series FR 500 Thermostatic Freeze Relief Kits are designed to keep water from freezing in the backflow preventer, while avoiding discharges based on the air temperature dropping below freezing. Series FR 500 thermostatically measures the water temperature and opens at 35°F and closes at 40°F. Maximum working pressure is 175 psi. Available sizes are 1/8, 1/4, 1/2 and 3/4 in. The FR 500 is compact, easy to install, low-maintenance and IAPMO-approved.
Watts Regulator Co.