InstallationQuestion 33 of 110
On a long vertical suction riser, what feature helps ensure compressor oil returns properly?
a.A larger condensate trap
b.Correct line sizing to maintain adequate refrigerant velocity
c.Extra thermostat wire
d.A bigger air filter
Explanation
Oil circulates with the refrigerant and must be carried back to the compressor by adequate vapor velocity, especially in vertical suction risers. If the line is oversized, velocity drops and oil pools, starving the compressor of lubrication. Proper sizing, and traps where required by the manufacturer, maintain oil return.
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