The pressure relief valves protect hot water storage heaters from internal overpressure. Furthermore, they restrict or prevent (according to requirements) water returning to main supply piping. Pressure relief valves essentially consist of 8 main devices: 3 controlling flow and 5 safety devices. The combination of these devices permits realisation which will satisfy customer’s requirements.
1. Water flow control device
This device controls and runs passage of water from inlet source to water heater when on it’s inside the pressure become lower for 0,1±0,2 bar (0,01 ±0,02 MPa), and in the same time it runs or pre vent water to go back into inlet source when the pressure inside water heater become higher for 0,8±1,5 bar (0,08±0,15 MPa).
2. Discharge pressure device (Safety)
The function of discharge pressure device is to avoid excessive pressure increment inside water heater. Calibration setting of discharge device is reached by compression of a spring to the standard value of opening 8,5 bar with tolerance ± 1 (0,85 MPa ±0,1). This value can vary and be set according to the client’s request. The device is sealed with disc to prevent from tampering. Should the seal be removed and the setting altered the maximum opening won’t be higher than 12 bar (1,2 MPa). During the testing the value of calibration setting is took on the second opening of discharge pressure device. During the phase of discharge, device becomes again watertight when the pressure decrease for 1 bar (0,1 MPa) in respect of standard opening value 8,5 bar ±1 (0,85 MPa ±0,1) All valves are calibrated and tested automatically before being packed and we guaranty high quality standards constant in quantities and time.
The body is made of hot moulded BRASS UNI EN 12165CW617N. Direction of the water flow. The surface is nickel – plated. Available (according to type) with threaded connections: 1/2 ” -3/4 ” -1 ” Gas. The valve body is designed to withstand internal pressure up to 16 bar (1,6MPa ). Maximum working temperature of the assembled valve : 120° C. The valve is automatically calibrated and checked during assembling. Further testing in percentage is carried out once assembling is finished.