Type II — High-PressureQuestion 152 of 240
A technician measures subcooling of 3°F on a TXV-equipped R-410A system when the manufacturer specifies 10°F of subcooling. What does the low subcooling most likely indicate?
a.The system is overcharged
b.There is too much liquid in the condenser
c.The system is likely undercharged (low on refrigerant)
d.The TXV is oversized
Explanation
On a TXV system, subcooling lower than the manufacturer's target usually means the system is undercharged, because there is not enough liquid backing up in the condenser to be subcooled. The technician would add refrigerant slowly and recheck subcooling. High subcooling, by contrast, generally indicates an overcharge.
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