Re-Installation While The Outdoor Unit Need To Be Repaired - Midea M2OC-18HFN1-M Service Manual

Procedure
1). Confirm that both the 2-way and 3-way valves
are set to the opened position
Remove the valve stem caps and confirm that the
valve stems are in the opened position.
Be sure to use a hexagonal wrench to operate the
valve stems.
2). Connect the charge hose with the push pin of
handle lo to the 3-way valves gas service port.
3). Air purging of the charge hose.
Open the handle Lo valve of the manifold valve
slightly to purge air from the charge hose for 5
seconds and then close it quickly.
4). Set the 2-way valve to the close position.
5). Operate the air conditioner at the cooling cycle
and stop it when the gauge indicates
0.1Mpa(14.5Psi)..
6). Set the 3-way valve to the closed position
immediately
Do this quickly so that the gauge ends up indicating
0.3Mpa(43.5Psi) to 0.5 Mpa(72.5Psi)..
Disconnect the charge set, and tighten the 2-way
and 3-way valve's stem nuts.
Use a torque wrench to tighten the 3-way valves
service port cap to a torque of 18N.m.
Be sure to check for gas leakage.
2. Air purging by the refrigerant
Procedure:
1). Confirm that both the 2-way and 3-way valves
are set to the closed position.
2). Connect the charge set and a charging cylinder
to the service port of the 3-way valve
Leave the valve on the charging cylinder closed.
3). Air purging.
Open the valves on the charging cylinder and the
charge set. Purge the air by loosening the flare
nut on the 2-way valve approximately 45' for 3
seconds then closing it for 1 minute; repeat 3
times.
After purging the air, use a torque wrench to tighten
the flare nut on the 2-way valve.
4). Check the gas leakage
Check the flare connections for gas leakage.
5). Discharge the refrigerant.
Close the valve on the charging cylinder and
discharge the refrigerant by loosening the flare
nut on the 2-way valve approximately 45' until the
gauge indicates 0.3Mpa(43.5Psi) to 0.5
Mpa(72.5Psi)..
6). Disconnect the charge set and the charging
cylinder, and set the 2-way and 3-way valves to
the open position
Be sure to use a hexagonal wrench to operate the
valve stems.
7). Mount the valve stems nuts and the service port
cap
Be sure to use a torque wrench to tighten the
service port cap to a torque 18N.m.
Be sure to check the gas leakage.
6.7 Re-installation while the outdoor unit
need to be repaired
1. Evacuation for the whole system
Procedure:
1). Confirm that both the 2-way and 3-way valves
are set to the opened position.
2). Connect the vacuum pump to 3-way valve's
service port.
3). Evacuation for approximately one hour. Confirm
that the compound meter indicates -0.1Mpa
(14.5Psi).
4). Close the valve (Low side) on the charge set,