Mitsubishi Electric PUHY-P250YNW-A Service Handbook page 243

[8-11 Measures for Refrigerant Leakage ]
(8) After repairing the leak, replace the dryer with the new one, and perform evacuation inside the
outdoor unit and optional unit.
(9) To adjust refrigerant amount, open the service valves (BV1 and BV2 when optional unit is in-
stalled) inside the outdoor unit.
When the power to the outdoor/indoor unit must be turned off to repair the leak after closing the service valves specified in
(4), turn the power off in approximately one hour after the outdoor/indoor units stop.
1) When 30 minutes have passed after (4) on the previous page, the indoor unit lev turns from fully closed to slightly open to
prevent the refrigerant seal.
LEV2 open when the outdoor unit remains stopped for 15 minutes to allow for the collection of refrigerant in the outdoor unit
heat exchanger and to enable the evacuation of the outdoor unit heat exchanger.
If the power is turned of in less than 5 minutes, LEV2 may close, trapping high-pressure refrigerant in the outdoor unit heat
exchanger and creating a highly dangerous situation.
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.
44
- chapter 8 BS_08_C