AUX air conditioner service manual
11
Slippage temp. 0 <0.17 4 6
Capacity of refrigeration
%
100 141 101
COP % 100 92.5 97
Lubricating oil Mineral oil POE POE
Lubricating oil
Mutual solubilization Good Fair Fair
2. The theory of refrigeration
There are many methods in artificial refrigeration. The most popular one among of them applied in
practice is the steam-compressing type. It completes the refrigeration task with the help of some fluid
of low evaporating temperature which can maintain a stable temperature while absorbing and reducing
the quantity of heat from the surrounding mediums during evaporate period. The temperature
reduction function of the air-conditioner is mainly realized by the refrigerating cycle. The
steam-compressing model refrigeration system, as shown in Picture 2-1, includes the most essential
refrigerating cycle composed of four parts: 1.Compressor; 2.Condensor 3.Throttle device Capillary
tube or expansion valve 4.Evaporator which are connected in turn by the pipes and form an airtight
system.
Its working process is: The liquid refrigerant absorbs the quantity of heat from the evaporator and then
will be gasified as gas at a low pressure and temperature. The compressor will suck this gas from the
sides of the evaporator and compress the gas (The pressure will turn high at the moment) through its
mechanism energy transferred from the electricity energy. With no stop, the mechanism energy turns
into the heat energy for increasing the temperature of the compressed gas (Super- heating gas) and
force it enter into the condenser. The compressed gas with high pressure and temperature will
undertake the heat exchange (heat release) process with the air (or heat source) around the condenser
and will be cooled and condensed as liquid with high pressure and middle temperature (Super-heating
gas, about 95 )→saturated→gas→wet→gas→saturated liquid→super-cooling liquid 46 , the
pressure value basically maintain the same (About 19Kgf/cm, and temperature is down). Because the
narrow diameter of the capillary tubes creates the resistance during the flow of the processed high
pressure and super-cooling refrigerant, the speed of the refrigerant flow will be accelerated, the
pressure will be lower down, the temperature will fall and accompanied with the tiny gasify
phenomenon. The refrigerant’s temperature about 7 5Kgf/cm , after passing through the
evaporator, will be lower than the ambiance temperature, and will turn into a gas state gradually from
the low pressure and wet steaming state after having sucked the heat from the ambiance mediums that
accelerate its gasify process. The way of its heat-absorbing results in the decline of the ambiance
temperature and consequently achieves the target of air-conditioning.
As the description of the above, the refrigeration system is continuously circulating by the way of
compressing →condensing→throttling →evaporating→compressing. With the function of promoting
the pressure of the refrigerant and transferring the refrigerant into continuous circulation, the
compressor is the heart of the whole system. The throttling components undertake the function of
flow-throttling, pressure-reduction and flow quantity –adjusting towards to the refrigerant entering
into the evaporator. However, the refrigerant is the blood of the refrigerating cycle for taking the
responsibility of transferring the quantity of heat; It releases the heat absorbed from the evaporator and
the one produced by the compressor to the air around the condenser for realizing the target of
refrigeration by continuously absorbing heat from low temperature mediums and releasing heat to the