408a

[the cooler]

can someone help me with a small problem retrofit a walk in freezer from 502 to 408a no info of charge on unit

[oilzee]

Dear The Cooler ,

Welcome to the RE . I have just retrofit 502 to 408a one month ago .
Before i did the triple evacuation i change filter drier , change compressor oil ( 3 GS ) .
I refill liquid to the system untill sight glass full ( 3/4 cans R408a, 3 Hp Bitzer compressor ) and got the result 6 TD evaporator temperature when reach to setting temperature , 17k at suction line inlet of compressor .
I used full day to monitor the evaporating superheat ( adjusted expansion valve ). The pressures almost same like before retrofit .
I had not change expansion valve .

Regards
oilzee