Type II — High-Pressure第 154 / 240 题
A technician performs a standing pressure (leak) test on a repaired Type II system using dry nitrogen. Over several hours the pressure holds steady with no drop. What does this indicate?
a.The system definitely needs more refrigerant
b.The nitrogen has turned to liquid
c.There must be a large leak
d.No detectable leak is present, so evacuation and charging can proceed
解析
A standing pressure test that holds steady over time (after correcting for temperature changes) indicates no detectable leak. The technician can then evacuate and charge the system. A pressure drop, by contrast, would signal a leak that must be found and repaired before charging.
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