Room precision air conditioning to room temperature and relative
The below room precision air conditioning components Xiangjie:
(A) a compressor
The compressor according to their structure is divided into three categories: open, semi-enclosed, fully enclosed. Currently most of the room for air conditioning Hermetic compressor.
Hermetic Compressor A compressor with motor device in a closed Hulled formed a whole. The only compressor suction and discharge fittings and motor wires from the outside; compressor housing is divided into two parts, compressor and motor load, up and down Hulled electrically welded into one. Usually can not be demolished, machine use and reliable.
Hermetic refrigeration compressor, and piston-type compressors and scroll compressors.
Hermetic scroll compressor refrigeration, its structure consists of the following: rotary inlet and outlet valve; pressure gauge interface; built-in overload protection; elastic base; crankcase heater; built-in lubricating oil pump .
Scroll refrigeration compressors biggest advantages are:
1, the structure is simple: only two components (dynamic disk, fixed disk) can be replaced by 15 parts of the piston compressor compressor body.
2, and efficient: the inspiratory gas and the conversion processing gas are separated, in order to reduce the heat transfer between the suction and handling, can improve the efficiency of the compressor. The scroll compression process and the conversion process is very quiet.
(B) an evaporator
1, the classification of the evaporator:
An evaporator in which it is cooled media types can be divided into the evaporator (dry evaporator) of the cooling liquid and the cooling air used in the evaporator (Table cooled evaporator) these two categories.
The CRAC system used by the evaporator is generally of the evaporator of the cooling air. When fed to the evaporator in the refrigeration system of the flon liquid enters the expansion valve is throttled, belonging to the vaporization process, this time need to absorb large amounts of heat, so that the room temperature is gradually reduced, in order to achieve the effect of refrigeration and dehumidification.
2, A-type evaporator
The advantages of the type "A" structure of the evaporator is that the structure has a larger frontal area and lower face velocity to prevent the upwind with water. The evaporator is equipped with a 1/2 "copper tube aluminum fin and stainless steel condensate tray, in order to facilitate better heat transfer.
Evaporator coil is divided into multiple access for staggered arrangement, whereby each refrigeration system can be all over on the windward side of the coil, when the single refrigeration system running, the sensible heat of the cooling capacity of up to 55% of the total cooling capacity -60%.
3, the dehumidification function of the evaporator
In the normal refrigeration cycle, the indoor unit fan is operating at a normal speed, in order to meet the required amount of refrigerant supplied to design gas stream and the most economic energy.
(1) simple dehumidification function
When dehumidification is required, the compressor is running, but the indoor unit of the motor rotational speed is reduced, is usually 2/3 of the original speed, the air volume is also reduced by 1/3, and through the cooling coil of the air temperature becomes too cold to produce good the condensing effects that increase the amount of desiccant.
The disadvantages of this method to increase the dehumidifying amount brought: when the air volume is reduced by 1/3, usually within a few seconds, the supply air temperature is reduced 2oC-3oC, when the sudden decrease in the temperature speed reaches the maximum allowed value reduced by 1 every 10 minutes ℃, resulting in the control reduced reliability; When the air volume is reduced by 1/3, lower filtration efficiency, on the number of ventilators and ventilation rate has a great impact, causing indoor control precision and uneven temperature distribution; temperature is reduced due to the wind need turned on the electric heater to raise the room temperature, resulting in temperature control imprecise and increased operating costs.
(2) dedicated dehumidification cycle
Cooling windings are divided into the upper, the next two parts, namely, the total cooling winding L / 3 and 2/3. Normal cooling mode, refrigerant flows through the cooling winding two parts. In the dehumidification mode, the normally open solenoid valve is closed, leading to the cooling the upper part of the winding coil (1/3 portions) so put Freon refrigerant is cut off, and all flon refrigerant flows to the cooling the lower part of the winding of the winding (2 / 3) section. The temperature of the air through the lower windings is low, typically at least lower than the air in the cooling cycle 3oC, and therefore increased the desiccant effect, but its drawback is that the total cooling capacity will be reduced and the suction pressure is reduced.
(3) bypass gas regulator
At the top of the "A" type evaporator install a bypass gas regulator, the regulator is turned off in normal cooling mode, all return the gas to be evenly through two cooling winding. When the dehumidifying operation, the bypass gas regulator is fully open, so that 1/3 of the return to the top of the winding of the gas bypass through the A box without going through cooling, the other 2/3 of the returning gas evenly through the windings of the A boxes, The exhaust gas temperature is rapidly decreased, to increase the dehumidification effect.