DL100 storage water heater thermostat is a multifunctional safety control with thermoelectric flame failure device, pressure adjuster and on-off regulating thermostat. No external electric power supply is required. TECHNICAL DATA Gas connections: Inlet 3/8 NPT (optional ½) Outlet 3/8 NPT (optional ¼) Water connections: ¾ NPT Max. working pressure: 50 mbar Working temperature: 0 - 85C Thermostatic range: 30 - 75C