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. mbsmproI 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. mbsmproI 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. mbsmpro
