REFRIGERANTS:- are heat carriers, used to transfer heat from the cabinet or room to the outside, utilizing the evaporation and condensation processes
The refrigerant used should have the ability to change phase easily from liquid to vapor and then from a vapor back to a liquid again
It should be non poisonous.
- It should be non explosives.
- It should be non corrosive.
- It should be non flammable.
- Leaks should be easy to detect.
- It should be non toxic.
Grouping and classification of refrigerants
Refrigerants have been classified by two different national organizations
a- National Refrigeration Safety Code (NRSC).
The national refrigeration safety code classified the refrigerants into three gropes
Group one: - safest of all refrigerants, it includes
R-11, R-12, R-22, R-500, R-502,
Group two:- toxic and some what flammable refrigerants
R-611 Methyl format
R-40 Methyl chloride
R-160 Ethyl chloride
R-1130 Dichloride ethylene
Group three: - flammable refrigerants
b- National Board of Fire Underwriters (NBFU).
The national board of fire underwriters classifies the refrigerants (mainly) on their degree of toxicity
11 R- 12 R- R-500