Wuxi Lneya solves the problem of how to charge refrigerants in the absence of refrigeration.
1. Connect all kinds of equipment well, close the three valve when the vacuum pressure is down to 133.3Pa, remove the hose from the suction port of the vacuum pump, connect it on the R404 cylinder, and release the hose on the three valve.
2. Open the handle on the R404 cylinder slightly, and when the R404 refrigerant sprayed out of the loosened hose, the loosened hose was quickly fastened to the three valve (this is to remove the residual air in the hose).
3. Invert the R404 gas cylinder, the explosion proof precision chiller compressor is electrified, and the power line is put into the clamp type ammeter. Open the three-way valve handle so that the compressor can quickly shut down after inhaling part of the R404 refrigerant. Observe the pressure gauge pressure and the clamp ammeter, and the three valve handles are reopened after the pressure and current are reduced. After filling a part of the R12 refrigerant, the handle of the three valve is quickly closed, repeated so several times.
4. Through comprehensive observation: the pressure of the pressure gauge is stable at 0.03-0.05MPa (0.02-0.04MPa in winter and 0.05-0.07 MPa in summer). When the current of the clamp ammeter is steady at 0.6-0.8A, the condenser is evenly distributed and the filter temperature is slightly higher than the ambient temperature. The evaporator surface is evenly frosted and it will feel sticky. At this time, the amount of refrigerant charge is appropriate, that is, the capillary can be compressed by sealing pliers, then the capillary can be clipped by wire clamp and welded by oxygen welding at the fracture.
5. The soapy water is used to check the welding place.
Follow the steps and the refrigerant filling of the explosion-proof precision chiller
should be completed basically, but it needs to be paid attention to that the refrigerant should not be overcharged at once in order to avoid failures.