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.There must be a large leak
c.The nitrogen has turned to liquid
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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