The GCA Mining nitrogen refrigerating unit is designed to be used in underground workings of coal mines, in workings of ‘a’, ‘b’ or ‘c’ level of methane explosion hazard and in workings of “A” or “B” class of coal dust explosion hazard. The unit is used for cooling nitrogen pumped into goafs to prevent fire in the area of a longwall in operation as well as in sealed headings. The unit is compact, made in closed housing on a frame bearer guaranteeing its stiffness during transport. The design of the unit enables its movement along with the longwall advance, it can also be installed in any gate road or in close proximity to the stopping if the area is sealed. The unit is powered from a typical mining starter. The refrigerating system is airtight, water used for cooling the condenser is taken from the mine system operating in an open circuit. The refrigerating unit can lower the temperature of nitrogen pumped into goafs by about 30 degrees to the recommended one [-1 C].