Asada ECOcycle Aurora II, Instruction Manual

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19
ECOcycle Aurora Ⅱ
RECOVERY
CYLINDER
● Refrigerant is a high pressure gas and mistakes in use or handling will lead to a serious accident.
Risk of overfilling
The pressure of the refrigerant varies depending on the ambient
temperature when the refrigerant is filled in a cylinder.
At this time, lowering of the liquid level by evaporation and rising
of the liquid level by specific volume increase occur at the same
time and balance.
At this time, rising of the liquid level by liquefaction and lowering
of the liquid level by specific volume decrease occur at the same
time and balance.
The right graph shows the relation between the pressure
(saturation pressure) and the temperature (saturation
temperature) for each kind of refrigerant.
This relation between the saturation pressure and the saturation
temperature is found when both liquid and vapor exist in a
cylinder. Normally the inside of the cylinder is under this
condition and this chart is useful for field operation.
When a cylinder is almost full with liquid and no vapor, the
pressure rises rapidly even with a slight increase in temperature.
This phenomenon must be avoided in any circumstances.
1）Relation between the temperature and the pressure of refrigerant in a cylinder
Temperature
rises
Some liquid refrigerant
evaporates
Pressure rises
Temperature
drops
Some vapor refrigerant
liquefies
Pressure drops
RECOVERY CYLINDER
-30
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
-0.1
Saturation pressure of liquid refrigerant
（MPa）
（Gauge pressure）
-20 -10 0 10
Saturation temperature of liquid refrigerant （℃）
20 30 40 50 60
R12
R502
R22
R134a
R407C
R410A
R404A
R507A
Saturation pressure and saturation temperature
of each type of refrigerant
Temperature and pressure
of refrigerant in cylinder
Saturated
vapor
Saturated
liquid
Saturated
vapor
Saturated
liquid
R22
23.8kg/cm
2
/337.85psi
at 60℃
R22
11.1kg/cm
2
/158.05psi
at 30℃
R12
6.6kg/cm
2
/94.25psi
at 30℃
R12
14.8kg/cm
2
/210.25psi
at 60℃
Solar
radiation
heat