外转子风机，是一种低噪音的新型风机，被传得神乎其神！好东西呀，在小功率的冷凝器以及蒸发器上有不错的表现！至于风量吗！似乎还有点不尽人意，不管怎么说它的确是一种改良的产品，相信在不远的将来会有更广泛的应用，

Expansion valve is the bottleneck of refrigeration system, its selection is very important, it is no exaggeration to say whether a system can work well and efficiently it plays a decisive role, the common expansion valve is divided into internal balance and external balance, internal Balance Expansion Valve is suitable for small evaporation resistance system, external balance expansion valve is suitable for large evaporation resistance system, expansion valve parameters should be selected according to the evaporator cooling capacity! In theory, the expansion valve cooling capacity should be slightly greater than the evaporator cooling capacity, but now the finished evaporator area generally shrink, especially the miscellaneous ceiling fan shrinkage problem is more serious! So in the choice of expansion valve should be considered when the problem, because the expansion valve refrigeration than the evaporator cooling capacity of more than 20% is a hidden danger! But this should be based on the actual situation of equipment to do some random adjustment, expansion valve selection, or small are not good, this range should be well controlled, cooling capacity matching is the ultimate goal! It is necessary to estimate the actual area and the actual refrigeration capacity of the evaporator to select the expansion valve. If the evaporator chooses a large refrigerant, it will evaporate prematurely, the refrigeration efficiency will decrease, and the degree of superheat will increase, that is, it will increase the dry consumption of food, and it will be disadvantageous to the cooling of the compressor, evaporator selection of small, and the risk of liquid hit, so in the selection of materials must choose regular manufacturers of high-quality products! Refrigeration compressor, it is the core of the condensing unit, it is a recovery of refrigerant pressure cycle pump! It seems simple but it is the heart of the whole system, the refrigeration cycle is normal operation, it is a credit to it, you do not underestimate it, this thing big knowledge! Let's talk about the most basic, the compressor is divided into high, medium and low temperature. Most manufacturers now produce medium and high temperature, or medium and low temperature compatible, and very few are high, medium and low temperature compatible, in the selection and use of refrigeration units, it is necessary to combine the actual needs with the rational selection of the temperature of the storeroom only in this way can we achieve high efficiency and energy conservation. For example, let's take the refrigerating units in the above table as an example to make a comparison to illustrate a misunderstanding, see BFS201 in the condensation temperature 30 degrees evaporation temperature-20 degrees of the refrigeration capacity is 21.8 kw, in the same operating conditions BFS301 refrigeration capacity is 47.8 kw, 30 HP machine cooling capacity than 20 HP more than double! What kind of a concept is that? This means that in this working condition, with two such 20HP middle temperature refrigeration unit is not a 30HP low temperature unit refrigeration capacity! This is the importance of equipment selection! External Rotor Fan, is a new type of low-noise Fan, has been legendary! Good thing, in the small power of the condenser and evaporator has a good performance! As for the air volume! It seems a bit unsatisfactory. In any case, it is indeed an improved product, and I believe it will be used more widely in the near future,