1. The HVAC pressure gauge accuracy level of the pressure gauge is selected based on the working pressure of the boiler or pressure vessel. When the working pressure of the boiler or pressure vessel is less than 2.5MPa, the accuracy level of the pressure gauge should not be less than 2.5; when more than 2.5MPa, the accuracy level not be less than 1.5. In other words, the higher the working pressure of the medium is, the higher the accuracy of the pressure gauge needs.
2. When selecting the dial scale range value of the HVAC pressure gauge, the dial scale limit value should be 1.5~2 times the working pressure of the medium. For example, when the boiler steam working pressure is 1.0 MPa, it is more appropriate to select the pressure gauge value range from 0 to 1.6 MPa. And the diameter of the pressure gauge dial used for installation on the boiler should not be less than 100~150.
1. The HVAC pressure gauge must be verified by the relevant measurement and verification department of the Labor Bureau before installation, and only qualified ones can be installed. The installed pressure gauge should be re-inspected regularly. It is not allowed to remove the lead seal for repairs or use uncalibrated pressure gauges for an extended period of time. And you need to choose a reliable pressure gauge manufacturer.
2. The HVAC pressure gauge should be installed in a location that is easy to observe and wash. And vibration and high-temperature baking should be avoided. There should be adequate lighting at the place where the HVAC pressure gauge is installed.
3. The HVAC pressure gauge should be installed in the steam space of the drum (steam drum), sub-cylinder, etc.. If on the pipeline, it must be installed on the straight section.
4. The HVAC pressure gauge is not allowed to be directly installed on the drum, sub-cylinder or pipeline. It should be connected to the water storage pipe (meter bend) and a three-way plug valve should be installed between the meter bend and the HVAC pressure gauge, and then connected with equipment or pipeline. The function of the surface bend is to accumulate the condensed water in the steam and prevent the steam from entering the spring tube directly, making it fail due to overheating. The three-way plug valve is convenient for flushing the pipeline and replacing pressure gauges.
5. When the HVAC pressure gauge shows that the needle cannot return to the zero position when there is no pressure, the dial scale is blurred, the protective glass is broken, the needle is stuck, etc., you should immediately replace the new watch to avoid misinformation and accident.