One very important tip. Do not attempt to start the unit whilst it is pressurized. The back pressure will stall the pump and eventually kill the motor. Always start with the bleed screw open and close it when the pump is spinning. The model that is in your photo is by the look of its features, is a Jufeng type. I have heard that Jufeng is the manufacturer that makes Yong Heng, Tuxing,Davv, and a few other brands. As for one or the other being better made, is not true. It's just a lottery like with a lot of Chinese goods, with if you get a good one or a bad one. I am sure that a lot of problems that have been experienced by users of these things, has been caused by ignorance, more than by dodgy product. It would be certainly worth their wild to supply a decent English speaking engineer to write proper owners manual for the things.
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