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5.6
Caution of the Pressure by Check Joint
When the pressure is measured, use the check joint of gas stop valve ((A) in the figure below) and use the
check joint of liquid piping ((B) in the figure below).
At that time, connect the pressure gauge according to the following table because of high pressure side and
low pressure side changes by operation mode.
Cooling Operation
Heating Operation
Check Joint for Gas Stop Valve "A"
Low Pressure
High Pressure
Check Joint for Piping "B"
High Pressure
Low Pressure
Check Joint for Liquid Stop Valve "C"
NOTE:
Be careful that refrigerant and oil do not splash to the electrical parts when removing the charge hoses.
Exclusive for Vacuum Pump and Refrigerant Charge
1. Maximum Permissible Concentration of HFC GAS R410A ,R410A is an incombustible
and non-toxic gas.
However, if leakage occurs and gas fills a room, it may cause suffocation. The maximum permissible
concentration of HCFC gas, R410A in air is 0.3kg/m
3
, according to the refrigeration and air conditioning facility
standard (KHK S 0010) by the KHK (High Pressure Gas Protection Association) Japan. Therefore, some
effective measure must be taken to lower the R410A concentration in air below 0.3kg/m
3
, in case of leakage.
2. Calculation of Refrigerant Concentration
(1) Calculate the total quantity of refrigerant R (kg) charged in the system connecting all the indoor units of
objective rooms.
(2) Calculate the room volume V (m
3
) of each objective room.
(3) Calculate the refrigerant concentration C (kg/m
3
) of the room according to the following equation.
If local codes or regulations are specified, follow them.
= C: Refrigerant Concentration
≤
0.3 (kg/m
3
)
R: Total Quantity of Charged Refrigerant (kg)
V: Room Volume (m
3
)
16
Summary of Contents for 3HRNM1Q
Page 2: ......
Page 3: ...23WB 43 DB 30 DB 17 WB 15WB 5 DB 15 DB 20 WB ...
Page 8: ...RAS 3HRNM1Q 1 Safety Summary 2 Structure Electronic Four way ...
Page 35: ......
Page 36: ...P00691Q 2013 11 V00 ...