Mitsubishi Electronics r410a Air Conditioner User Manual


 
[ IX Troubleshooting ]
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HWE09080 GB
2) Therefore, if the power source is turned off within 30 minutes, the lev remains fully closed and the refrigerant remains sealed.
When only the power for the indoor unit is turned off, the indoor unit LEV turns from faintly open to fully closed.
3) In the cooling cycle, the section between "21S4b, c" and "LEV 2a, b" will form a closed circuit.
To recover the refrigerant or evacuate the system, "LEV1" and "SV5b, c" will be open by setting SW5-8 to ON in the stop
mode.
Set SW5-8 to OFF upon completion of all work.
3. Leak spot: In the case of extension pipe for indoor unit (Heating season)<PQHY>
(1) Run all the indoor units in heating test run mode.
1) To run the indoor unit in test run mode, turn SW3-2 from ON to OFF when SW3-1 on the heat source control board is ON.
2) Change the setting of the remote controller for all the indoor units to the heating mode.
3) Check that all the indoor units are performing a heating operation.
(2) Stop all the indoor units, and stop the compressor.
1) To stop all the indoor units and the compressors, turn SW3-2 from ON to OFF when SW3-1 on the heat source control board
is ON.
2) Check that all the indoor units are stopped.
(3) Close the service valves (BV1 and BV2).
(4) Collect the refrigerant that remains inside the indoor unit. Do not discharge refrigerant into air into the atmosphere
when it is collected.
(5) Repair the leak.
(6) After repairing the leak, perform evacuation
*1
of the extension pipe for the indoor unit, and open the service valves
(BV1 and BV2) to adjust refrigerant.
4. Leak spot: In the case of heat source unit (Heating season)<PQHY>
1) Collect the refrigerant in the entire system (heat source unit, extended pipe and indoor unit).Do not discharge refrigerant into
the atmosphere when it is collected.
2) Repair the leak.
3) After repairing the leak, replace the dryer with the new one, and perform evacuation of the entire system, and calculate the
standard amount of refrigerant to be added (for heat source unit, extended pipe and indoor unit), and charge the refrigerant.
Refer to "VIII [4] 3. "
If the indoor or heat source units need to be turned off for repairing leaks during Step 1) above, turn off the power approxi-
mately 1 hour after the units came to a stop.
If the power is turned off in less than 15 minutes, LEV2a and LEV2b may close, trapping high-pressure refrigerant in the heat
source unit heat exchanger and creating a highly dangerous situation.
In the cooling cycle, the section between "21S4b, c" and "LEV 2a, b" will form a closed circuit.
To recover the refrigerant or evacuate the system, "LEV1" and "SV5b, c" will be open by setting SW5-8 to ON in the stop
mode.
Set SW5-8 to OFF upon completion of all work.
*1. Refer to Chapter I [8] Vacuum Drying (Evacuation) for detailed procedure.