Service Manual

11
1. Air purging with vacuum pump
1) Completely tighten the flare nuts of the
indoor and outdoor units, confirm that both
the 2-way and 3-way valves are set to the
closed position.
2) Connect the charge hose with the push pin
of handle lo to the 3-way valves gas service
port.
3) Connect the charge hose of handle hi
connection to the vacuum pump.
4) Fully open the handle Lo of the manifold
valve.
5) Operate the vacuum pump to evacuate.
6) Make evacuation for 30 minutes and check
whether the compound meter indicates -
0.1Mpa(14.5Psi). If the meter does not
indicate -0.1Mpa(14.5Psi) after pumping 30
minutes, it should be pumped 20 minutes
more. If the pressure can’t achieve -
0.1Mpa(14.5Psi) after pumping 50 minutes,
please check if there are some leakage
points. Fully close the handle Lo valve of
the manifold valve and stop the operation of
the vacuum pump. Confirm that the gauge
needle does not move (approximately 5
minutes after turning off the vacuum pump).
7) Turn the flare nut of the 3-way valves about
45° counterclockwise for 6 or 7seconds
after the gas coming out, then tighten the
flare nut again. Make sure the pressure
display in the pressure indicator is a little
higher than the atmosphere pressure. Then
remove the charge hose from the 3-way
valve.
8) Fully open the 2-way valve and 3-way valve
and securely tighten the cap of the 3-way
valve.
6.5 Adding the refrigerant after
running the system for many years
Procedure
1). Connect the charge hose to the 3-way
service port, open the 2-way valve and the 3-
way valve.
Connect the charge hose to the valve at the
bottom of the cylinder. If the refrigerant is
R410A, make the cylinder bottom up to ensure
liquid charge.
2). Purge the air from the charge hose.
Open the valve at the bottom of the cylinder
and press the check valve on the charge set to
purge the air (be careful of the liquid
refrigerant).
3) Put the charging cylinder onto the electronic
scale and record the weight.
4) Operate the air conditioner at the cooling
mode.
5) Open the valves (Low side) on the charge
set and charge the system with liquid
refrigerant.
6). When the electronic scale displays the
proper weight (refer to the gauge and the
pressure of the low side), disconnect the
charge hose from the 3-way valve’s service port
immediately and turn off the air conditioner
before disconnecting the hose.
7). Mount the valve stem caps and the service
port
Use torque wrench to tighten the service port
cap to a torque of 18N.m.
Be sure to check for gas leakage.