UNITDAMAGEHAZARD
Failuretofollowthis caution may result in equipment
damage or improper operation.
Never use the system compressor as a vacuum pump.
Refrigerant tubes and indoor coil should be evacuated using the
recommended deep vacuum method of 500 microns. The alternate
triple evacuation method may be used if the procedure outlined
below is followed. Always break a vacuum with dry nitrogen.
SYSTEM VACUUM AND CHARGE
Using Vacuum Pump
1. Completely tighten flare nuts A, B, C, D, (for all fan coils).
Connect gage charge hose to one circuit or all circuits (if
using a nmltiple connection manifold) at the low side ser-
vice valve charge port(s). (See Fig. 14.)
2. Connect charge hose to vacuum pump.
3. Fully open the low side of manifold gage. (See Fig. 15)
4. Start vacuum pump
5. Evacuate using either deep vacuum or triple evacuation
method.
6. After evacuation is complete, fully close the low side of
manifold gage and stop operation of vacuum pump.
7. If nmltiple connection manifold is not used, repeat the pro-
cedure (1 through 6) until all indoor units and piping are
completely vacuumed.
8. The factory charge contained in the outdoor unit is suitable
for max pipe length as shown on page 3 of this document.
If additional charge is required, it should be added to the
system as liquid at this time.
9. Disconnect charge hose from charge connection of the low
side service valve.
10. Fully open all service valves.
11. Securely tighten caps of service valves.
Outdoor Unit Refrigerant Indoor Unit
[_ _T_& LowSide D_
_2:_ B High Side
Service Valve
A07360
Fig. 14 - Service Valve
Manifold Gage
500 microns d/: _
LOWside valve _'_ )) "_
__._7 High side valve
Charge hose-_ \\_ Charge hose
[ i__ \\l/.__Vacuumpump\\Y
Low side valve
Fig. 15 - Manifold
A07361
Deep Vacuum Method
The deep vacuum method requires a vacuum pump capable of
pulling a vacuum of 500 microns and a vacuum gage capable of
accurately measuring this vacuum depth. The deep vacuum method
is the most
liquid water.
o)
Z
O
iv.
O
m
=;
)ositive way of assuring a system is free of air and
See Fig. 16)
LEAK IN
SYSTEM
VACUUM TIGHT
TOO WET
TIGHT
DRY SYSTEM
0 1 2 3 4 5 6 7
MINUTES
Fig. 16 - Deep Vacuum Graph
A95424
Triple Evacuation Method
The triple evacuation method should only be used when vacuum
pump is only capable of pumping down to 28 in, of mercury
vacuum and system does not contain any liquid water.
Refer to Fig, 17 and proceed as follows:
1. Pump system down to 28 in. of mercury and allow pump to
continue operating for an additional 15 minutes.
2. Close service valves and shut off vacuum pump.
3. Connect a nitrogen cylinder and regulator to system and
open until system pressure is 2 psig.
4. Close service valve and allow system to stand for 1 hr. Dur-
ing this time, dry nitrogen will be aMe to diffuse throughout
the system absorbing moisture.
5. Repeat this procedure as indicated in Fig. 17. System will
then be free of any contaminants and water vapor.
IEVACUATE I
l BREAK VACUUM WITH DRY NITROGEN I
IEVACUATEI
IBREAKVACUUMWITHDRYNITROGE"I
IEVACUATEI
I CHECK FOR TIGHT, DRY SYSTEM I
(IF IT HOLDS DEEP VACUUM)
I RELEASE CHARGE INTO SYSTEM I
A95425
Fig. 17 - Triple Evacuation Method
Final Tubing Check
IMPORTANT: Check to be certain factory tubing on both indoor
and outdoor unit has not shifted during shipment. Ensure tubes are
not rubbing against each other or any sheet metal. Pay close
attention to feeder tubes, making sure wire ties on feeder tubes are
secure and tight.
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