I charged the compressor CAJ4519Z with R407 gas, and upon startup, some frost appeared on the return line and expansion valve, even though the cooling was fine. Is this normal? Note that it’s a refrigeration room, not a freezer.

 The Tecumseh CAJ4519Z stands as a benchmark in commercial refrigeration, offering robust performance for Medium and High Back Pressure (MHBP) applications. Engineered for versatility, it supports a wide array of refrigerants including R404A and R407C. This professional analysis covers technical data, wiring configurations, and essential maintenance practices for field engineers…