Carrier 69NT40-561-019, Operation And Service Manual

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7–1 T-359
SECTION 7
SERVICE
7.1 SECTION LAYOUT
NOTE
Use a refrigerant recovery system whenever removing refrigerant. When working with refrigerants you
must comply with all local government environmental laws. In the U.S.A., refer to EPA section 608.
CAUTION
!
Never use air for leak testing. It has been determined that pressurized, mixtures of refrigerant
and air can undergo combustion when exposed to an ignition source.
Service procedures are provided herein beginning with refrigeration system service, then refrigeration system com-
ponent service, electrical system service, temperature recorder service and general service. Refer to the
Table of
Contents to locate specific topics.
7.2 MANIFOLD GAUGE SET
The manifold gauge set ( Figure 7.1 ) is used to determine system operating pressure, add refrigerant charge, and
to equalize or evacuate the system.
Figure 7.1 Manifold Gauge Set
1. Opened (Backseated) Hand Valve
2. Suction Pressure Gauge
3. Discharge Pressure Gauge
4. Closed (Frontseated) Hand Valve 5. Connection to high side of system
6. Connection to either:
a. Refrigerant cylinder OR
b. Oil Container
7. Connection to low side of system
- - - - -
When the suction pressure hand valve is frontseated (turned all the way in), the suction (low) pressure can be
checked. When the discharge pressure hand valve is frontseated, the discharge (high) pressure can be checked.
When both valves are open (all the way out), high pressure vapor will flow into the low side. When the suction pres-
sure valve is open and the discharge pressure valve shut, the system can be charged. Oil can also be added to the
system.
A R-134a manifold gauge/hose set with self-sealing hoses ( Figure 7.2 ) is required for service of the models cov-
ered within this manual. The manifold gauge/ hose set is available from Carrier Transicold. (Carrier Transicold part
number 07-00294-00, which includes items 1 through 6,
Figure 7.2 .) To perform service using the manifold gage/
hose set, do the following:
1
2
3
4
5
6
7