Domestic refrigeration.

[B0bbyDrake]

2 questions.

1) When charging a domestic refrigeration unit, do you have the compressor running?

2) When charging, do you have the can of R600a upside down?

Also, why do you advocate doing these actions?

[seanf]

1. If there is enough pressure in the refrigerant can/cylinder to charge the full amount, then you can just leave the compressor off.
If your charging liquid refrigerant into the compressor port then flash it off by throttling it in.
If you suspect liquid refrigerant is sitting in the compressor, leave it to boil off before starting the compressor.
If you have to run the compressor to pull in the refrigerant, again if charging liquid, carefully throttle it in.

2. Yes, the small cans of R600a can be put upside down to charge. You can get a weigthed bottle adaptor for them.
For cylinders (like 20kg of refrigerant) you need to check if its vapour only, liquid only, or separate liquid and vapour ports on the cylinder.

Probably not so common on domestics, but along with the suction port on the compressor you might find a access port on the liquid line. Where you can charge liquid refrigerant without having to be so carefully as when charging liquid into the compressor.