For steam and hot water boilers with cold water feed|Continuous maintenance of minimum safe water level, independent of electrical service|Proportional feed action|Quick hook up fittings provided|Quick-change replaceable cartridge valve and strainer|Model 47 can be field upgraded with a No 2 switch to add low water cut-off function|Maximum water supply pressure 150 psi (10.5 kg/cm2)|Maximum inlet water temperature 120 deg F (49 deg C)|Maximum boiler pressure 25 psi (1.8 kg/cm2)
McDonnell & Miller Mechanical Water Feeder, 120 deg F, 150 psi