Installation For The First Time; Adding Refrigerant After The System Has Been In Service - COMFORT-AIRE A-DVC24SF-1 Service Manual

Service Manual - DVC 09/12/18/24 SF Series

5.4 Installation for the first time

Air and moisture in the refrigerant system have
undesirable effects as below:
● Pressure in the system rises.
● Operating current rises.
● Cooling or heating efficiency drops.
● Moisture in the refrigerant circuit may
freeze and block capillary tubing.
● Water may lead to corrosion of parts in the
refrigerant system.
Therefore, the indoor units and the pipes
between indoor and outdoor units must be leak
tested and evacuated to remove gas and
moisture from the system.
Gas leak check (Soap water method):
Apply soapy water or a liquid neutral
detergent on the indoor unit connections
and outdoor unit connections by a soft
brush or spray to check for leakage of the
connecting points of the piping. If bubbles
appear, the pipes have leakage.
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 low pressure handle to the 3-way valves
gas service port.
3) Connect the charge hose of high pressure
handle connection to the vacuum pump.
4) Fully open the low pressure handle of the
manifold valve.
5) Operate the vacuum pump to evacuate.
6) Evacuate for 30 minutes and check whether
the compound meter indicates 300
microns. If the meter does not indicate
300 microns after pumping 30 minutes,
it should be pumped 20 minutes more. If the
pressure can't
after pumping 50 minutes, please check if
there are some leakage points.
Fully close the low pressure handle of the
manifold valve and stop the operation of
the vacuum pump. Confirm that the gauge
needle does not
minutes after turning off the vacuum pump).
7) Turn the flare nut of the 3-way valves about
45° counterclockwise for 6 or 7 seconds
after gas comes out, then tighten the flare
nut. Make sure the pressure display in
the pressure indicator is a little higher
than the atmosphere pressure.
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.
5.5 Adding refrigerant after the system
has been in service
17
19
achieve 300 microns
move (approximately
Then
5