Cryogenics -80

[dakesojo]

Hi can anyone help i need to find out the refrigerant charge as the unit that a compressor change,the refrigerant says mixture and amount of 0.260 Grams.I have spoken the the uk importer and he has no info on.
Its a single stage unit that only needs one compressor with two circuits (like a cascade system)
Unit detail
Make-zhongke meiling cryogenics
Model-DW-HW50
Ps i have removed the refrigerant which has a smell of propane

Could i use R508b ?

[install monkey]

r290,r600 mix or 5o8b usually -80 kit is 2 stage cascade- 404a for high stage
no nameplate on the cabinet?
last resort check with manufacturers as if it doesnt work its gonna take ages to get to temp

[al]

Propane keeps the oil flowing, it'll need a small amount from vacuum, maybe only a gauge line full. Recommended charge and type of refrigerant is vital, don't guess at -80. Sounds chinese so god only knows what was in it originally.

alec