regassing display fridge

[jack-ice]

Hi, I am new to working on smaller fridges and have a quick question on regassing a display fridge.It has a single port coming off the compressor which i presume is the low side charging port..is it possible to just top up through that port with compressor shut down or does it have to be done after full recovery and vac??? There are no leaks as the fridge was undercharged and just requires top up.

thanks.

[toprunner]

If you have a device that can inject refrigerant with a higher pressure than your low side pressure... yes!

How can you make the assumption about undercharged?

[jack-ice]

I have not seen the fridge yet but was told that when it was regassed they didn't have enough refrigerant left in the bottle, i will know for sure when i gauge up. Will the bottle pressure be enough to force it in through the low side? I think its only 1kg bottles so im presuming it will have to be vaccumed before it will take the gas.

[james10]

You need to overcome pressure in the system let the refrigerant in untill pressure between system and bottle equalise then put your 1kg bottle in a bucket of warm water and it'll fly in.