Product Description The compact and economical Cash Acme F-30 pressure relief cave is intended for use on hot water space heating boilers, water heaters, and storage tanks. The F-30 is factory set to 30 PSI and is NB listed to the ASME boiler code section IV. The valve is designed for hot water service only and is not for use on steam. From the Manufacturer Female connections, bronze body, and silicone seat. Designed for maximum intermittent water pressure of 125 psi.