HVAC engineers

Pressure Gauges Pressure gauges are connected to pipes to physically display the flow pressure - particularly the static pressure. Why do we need to monitor pressure in the first place? Pressure reading before and after equipment can indicate whether the component is running correctly or not. A high pressure drop is usually a result of a clog or a leak somewhere. To select a pressure gauge, two parameters are most important: accuracy and range. The range of a pressure gauge is the maximum pressure reading possible on that gauge. It is a good practice to aim for a range that is 1.5-2 times the system's working pressure, with the maximum allowed pressure somewhere in the range. (relief valve pressure) The accuracy of a pressure gauge is expressed by a +/-percentage of error in the pressure reading. For accuracy, ASME (American Society of Mechanical Engineers) has set standard classes for pressure gauges. Grades B, 1A & 2A. In a typical chilled water system, Grade B gauges do the ...