While most of the time, when you think about refrigeration, you probably consider how your home fridge works. However, you should know that when it comes to Blast Chillers, walk-in coolers actually work much differently. Instead of using the cold air that is created by the freezer unit, a walk-in cooler actually generates the cold air it needs to maintain the temp that the thermostat is set at. The condenser and fans create the cold air, very much like a window AC unit would do- the condenser unit cycles on and off, maintaining the temp.
The thermostat is what determines the temp of the walk-in cooler. Once the temp gets higher than the thermostat, the condenser unit turns on, which starts a new cooling cycle. The fans of the unit pull air into it and over those condenser coils, which pulls the heat from the air. Then, the cooled air moves out the back of the unit, much cooler than it was when it first entered. As the fans blow the air over the condenser, the temp in the cooler keeps lowering until it’s once again below the level that has been set by the thermostat. The coolant in the coils is pumped continually during the cooling cycle. This helps to ensure that the coolant doesn’t warm up too much before cooling down again.
There is a second cycle in the cooling process that is in place to keep the condenser from freezing up, becoming covered in ice and frost. When/if the thermostat ends up going too low, the fans will begin again, but the coolant will not be cycling. This will gradually warm the coils. This is known as defrosting and when you have Blast Chillers, this will continue until the temp falls into a decent range once again.