18
1. Maximum Permissible Concentration of HFC GAS R410A charged in the DC INVERTER 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
)
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 at removing the charge hoses.
Exclusive for Vacuum Pump and Refrigerant Charge
Summary of Contents for JDOH Series
Page 2: ......
Page 19: ...JE 102SN JE 162SN ...
