Refrigeration Evaporators is a main heat exchanger used in the refrigeration system, which directly affects the efficiency of the refrigeration system. As we all know, the air cooler will use different fin spacing according to the required cold room temperature.Widely used fin spacing is 4mm, 4.2mm, 6.4 ~ 8mm,9.0mm, 10mm, 12mm. If the  cold storage temperature lower, the fin spacing larger. If the selection is unreasonable, the fins will frost quickly, and the passage of the wind will soon be blocked. It is difficult to cool the cold storage, and the compressor efficiency will reduce, resulting in increased power consumption in the refrigeration system.

According to engineering experience, generally 0 ℃ ~ 20 ℃ chiller room, such as workshop air conditioner, cool warehouse, cold storage room, fresh storage warehouse, air conditioning warehouse, ripening warehouse, etc., choose a fan with a blade distance of 4mm or 4.2mm; -16 ℃ ~ -25 ℃ cold freezer room, such as low-temperature freezing and refrigeration, low-temperature logistics warehouse, choose a fan with a blade distance of 6mm ~ 8mm; quick-freezing warehouse at -25 ℃ ~ -35 ℃, generally choose a fan with a blade distance of 9mm,10mm and 12mm

However, on some occasions, it is not possible to select the fin spacing of the cooler simply by temperature, such as quick pre-cooling of meat and vegetables, and acid discharge, although the temperature of the cold room is generally set above 0 ℃, but  the incoming temperature is higher and required quicker cooling， the humidity of the goods is high. If you choose a cooler with a fin space of 4mm ,4.2mm or 4.5mm, it is not suitable. You must use a cooler with a pitch of 8mm,9mm or even 10mm. Unless the fin will easily be defrosted.

Garlic and apples storage temperature is generally -2 ℃. For such fresh-keeping or modified atmosphere warehouses with a storage temperature lower than 0 ℃, evaporator fin space should not less than 8mm. To avoid power consumption and the blockage of the air duct caused by rapid frost.