Trane TTD, Installation Manual

Page: 9 / 20

MS-SVN005-EN
9
System Evacuation and Purping
The outdoor unit is factory charged.
Unit nameplate charge is the total
required system charge with 7.5
meters of interconnecting lines. Since
the outdoor unit will not have to be
evacuated unless charge has been
completely lost, leave the suction and
liquid shut-off valves closed.
1. Upon completion of installation,
evacuate the refrigerant lines and
indoor coil (Figure 6).
2. Evacuate unit until the gauge reads
350 microns or evacuate at least
one hour for one system.
3. Close off valve to vacuum pump
and observe the micron gauge. If
gauge pressure rised above 500
microns in one (1) minute, then
evacuation is incompleted or
system is leaking.
- Attach appropriate hose from
manifold gauge to suction and
liquid line valves service ports.
- Attached center hose of mainfold
gauges to vacuum pump.
Note
Unnecessary switching of hoses and
complete evacuation of all lines
leading to sealed system can be
accomplished by placing a “T” in
manifold center hose and connecting
branch hose to cylinder of R-22.
Note
Evacuate unit 2 and 3 in the same
manner explained above.
This completes system evacuation
with a vacuum pump and the air
conditioner is ready for actual
operation.
Figure 6
Indoor Unit 3
Indoor Unit 2
Indoor Unit 1
System # 3
System # 2
System # 1
Service Port System #3
Suction Line System #3
Liquid Line System #3
Suction Pressure
Liquid Pressure
Vacuum Pump
Cylinder of R-22
MS-SVN005-EN.indd 9 1/10/08 11:03:33 AM