Replacement of the chiller system
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Two York chillers along with the associated piping have already been installed; we are now preparing to fill them with propylene refrigerant and lubricating oil. I would like to know whether I should use: 1. Nitrogen purging + vacuum pumping； 2. Nitrogen displacement + propylene displacement. Which of the two methods is better? With the second method, there are too many dead corners in the ice machine, which may lead to incomplete replacement, and it is also more complicated to operate. Please help!
I’ve never used a York chiller, but the principle is more or less the same. Option 2 is not recommended. Because once there is a dead corner, if there is moisture in that corner, ice blockage (freezing of water) may occur ； If there is air or nitrogen in the dead corners, it may lead to excessively high exhaust temperatures and pressures, resulting in a decrease in cooling capacity. Option 1 can be used under normal circumstances. For new systems, where there is a risk of excessive moisture in hidden areas, it is recommended to use triple evacuation. First, introduce nitrogen to test for leaks; once there are no issues, release the nitrogen. Then evacuate the space (the level of vacuum that can be achieved depends on the capacity of the vacuum pump and its pressure range) ； Then add nitrogen, discharge it again, and evacuate ； Add nitrogen and evacuate three times each. The purpose is to remove moisture from the system.
Is there a specific plan? Share it
Of course, the best solution is a small amount of propylene gas + vacuum replacement! First, evacuate the space, then introduce propylene (not fill it...); the propylene gas will fill the space, after which the area is evacuated again... and then filled once more!
Triple evacuation, I already said it
Evacuate non-condensable gases, fill with vacuum oil, introduce the medium