The filter purifies the coolant gas by removing acids, moisture, and particles from the dirty gas coming from the vehicle. The special stone material inside the drier filter loses its effectiveness after cleaning 150 kg of gas. Just as a sponge releases the rest of the water after absorbing enough, this type of gas purifying filter works the same way. When the device gives a warning, it must be replaced. Unlike filters in vehicles, the filter does not clog when its lifespan is over. Because the filter does not clog, it sometimes does not need to be replaced. Since the filter does not clog, it cannot clean and purify the gas because it has lost its function. If the gas that has not been purified is used again, sufficient cooling will not be obtained, and it may cause irreparable damage to the vehicle and the device.