Air Evacuation And Refrigerant Charge - Trane WTK507 Installation Manual

Service
hoses
10
Air Evacuation
and Refrigerant Charge
Evacuation
Air and humidity are the enemy of
the air-conditioning system because
humidity will react with R22 refrigerant
and turns into acid, which will corrode
the wire coil and reduce the
compressor oil's efficiency. Evacuation
is a must to prevent refrigerant system
from air and humidity.
Evacuation Procedure
Connect the middle hose of service
gauge to the vacuum pump, then
connect the hose at the low side to
"service valve" of air-conditioning
at suction line. Connect the hose at
the high side to "service valve" at
liquid line (figure 13).
Fill up R22 refrigerant into the
system
To fill up R22 refrigerant is the final
step of installation. After leakage
check and power wiring, fill up R22
refrigerant to the system.
How to fill up R22 refrigerant
Normally, this needs to be done
immediately after air evacuation per
the following steps (figure 13)
• Fill up the refrigerant via valve at
liquid line until pressure of the
liquid line is around 120-150 psig
(Don't forget to evacuate air from
liquid line before)
• Turn on evaporator and condensing
unit.
Liquid Liquid
line pressure
Suction
line
Electrical
connection
Figure 13
• Fill up the refrigerant into suction
• Let machine run for at least 20
If the pressure readings of both liquid
line and suction line are in the range
stated above and electric current
reading is at full load ampere of
condensing unit, it indicates that
refrigerant's volume is sufficient.
• But if suction pressure is lower than
• If suction pressure is higher than
Remark: When the interconnecting
line is longer than 7.5 m, additional
charging is necessary. For the additional
amount, follow the table belows.
Suction
pressure
Liquid-Suction
Vacuum pump
R22
line at the proper quantity while the
unit is working.
minutes. Read pressure from
pressure gauge "at both high and
low side", and read current
from amp-meter. Usually, suction
line pressure should be around
65-70 psig , and liquid line pressure
should be around 250-275 psig.
normal and electric current is far
below full load ampere, it indicates
that refrigerant is inadequate.
You need to add more refrigerant.
normal and electric current is over
the full load ampere, and you notice
some water spray holds on the
compressor, it indicates over cooling
system. You need to release some
refrigerant.
Piping Per each additional
size meter of
interconnecting line
grams/meter
1/4 - 3/8 23 grams/meter
é é
1/4 - 1/2 26 grams/meter
é é
3/8 é - 5/8 é 59 grams/meter
3/8 é - 3/4 é 60 grams/meter
3/8 - 1 1 / 68 grams/meter
é é
8
1/2 - 7/8 117 grams/meter
é é
WTK-SVN001-EN