The most important components of a coldroom must be the compressor and the condenser. You can compare the compressor to the human heart and the condenser as the lungs.
The role of a compressor in a coldroom system is to pressurize the refrigerant fluid. Acting like a pump, the refrigerant under pressure will heat up as it travels to the condenser. The hot refrigerant then radiates its heat within the condenser. The metal fins of the condenser help to speedup this process. The refrigerant flows back into the coldroom and goes through a thermostatic expansion valve, which causes the liquid refrigerant to vaporize. According to gas physics, any liquid that vapourise into a gas will cool down and the refrigerant absorbs heat inside the coldroom, lowering the interior temperature and the cycle continues.
The condenser purpose is to radiate heat out of the coldroom efficiently and reliably. A condensor is a passive component formed from metal in the shape of a hollow tube or plate that separates substances at two different temperatures.