Service manual

6-1
T-294-01
SECTION 6
SERVICE
NOTE
Toavoiddamagetotheearth’sozonelayer,usearefrigerantrecoverysystemwheneverremovingrefrigerant.
When working with refrigerants you m ust comply with all local government environmental laws. In the
U.S.A., refer to EPA section 608.
6.1 REPAIRING THE REFRIGERATION SYSTEM
The unit is designed as a hermetic system, which
reduces the number of potential leak-points for
refrigerant. The refore the suction service, discharge
service and manual liquid line valves have been
eliminatedincomparisontothe standardcontainerunit.
In conjunction, the sight glass on the water-cooled
condenser, andthefilter-drierquick--connect nuts have
also been removed. These areas have either been
completely eliminated, or have been replaced with
brazed joints.
To perform maintenance on the system, two process
tubeshave beenprovided, whichare theliquidline and
suctionline processtubes,seeFigure 6-4forlocations.
Refer to Table 6-4 for a list of t he tools required to
perform the t asks in sections 6.2, 6.3 and 6.4.
6.2 PIERCING VALVES
To gain access to the hermetic system, it is
recommended to use the Robinair P/N 40288 piercing
valve on the units process tubes.
a. Preparation
1. Tubing should be straight and round.
2. Carefully clean the process tubing where the
piercingvalvewillbeattached,doNOTscratchthe
tubing.
3. Make sure there are no dents in the tubing.
4. Apply a little clean refrigerant oil to the tubing
where the piercing valve will be placed.
b. Installing
1. Makesurethegasket(item2, refertoFigure 6-1)is
in place, and the piercing needle (item 3) is backed
all the way out by turning the hand valve (item 1)
counter-clockwise.
2. Remove the nut (item 5) and u-shaped block (item
4) from the base of the piercing valve.
3. Straddle the process t ube with the hand valve
portion of the piercing valve.
4. Install the u-shaped block and nut onto the baseof
the piercing valve that was removed in step 2.
5. Tightenthevalveto theprocess tubeby turningthe
nutenoughtosealthegasketandtosecurethevalve
to the process tube.
6. Do NOT overtighten. Overtightened valves can
actually cause a leak.
7. Installt hemanifoldgaugehose(refertosection6.3)
to the one-quarter inch connector (item 6) using a
low or high side R-134a connector (item 13 or 14,
Table 6-4), and a low or high s ide swivel elbow
(item 11 or 12).
8. Turn the hand valve clockwise to pierce the tubing
and access the refrigeration system.
1
2
3
4
5
6
1. Hand Valve
2. G asket
3. Piercing Needle
4. U-Shaped Block
5. Nut
6. One-Quarter Inch S.A.E. Connector
Figure 6-1. Piercing Valve
c. Removal
1. Reverse the steps in section 6.2.b.