Carrier 69NT40-561-300, Operation And Service Manual

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7–1 T-365
SECTION 7
SERVICE
NOTICE
Use a refrigerant recovery system whenever removing refrigerant. When working with refriger-
ants you must comply with all local government environmental laws. In the U.S.A., refer to EPA
section 608.
WARNING
!
EXPLOSION HAZARD Failure to follow this WARNING can result in death, serious personal
injury and / or property damage.
Never use air or gas mixtures containing oxygen (O
2
) for leak testing or operating the product.
Charge only with R-134a: Refrigerant must conform to AHRI Standard 700 specification.
7.1 SECTION LAYOUT
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.
Figure 7.1 Manifold Gauge Set
7.2 MANIFOLD GAUGE SET
The manifold gauge set (see Figure 7.1 ) is used to determine system operating pressure, add refrigerant charge,
and to equalize or evacuate the system.
When the Suction Pressure Valve is frontseated (turned all the way in), the suction (low) pressure can be checked
at the Suction Pressure Gauge.
When the Discharge Pressure Valve is frontseated, the discharge (high) pressure can be checked at the Discharge
Pressure Gauge.
When both valves are backseated (all the way out), high pressure vapor will flow into the low side.
Utility Connection to:
A. Refrigerant cylinder
B. Vacuum Pump
C. Oil Container
Discharge Pressure
Gauge
Suction Pressure
Gauge
Suction Pressure
Valve
(shown frontseated)
Low Side
Connection
High Side
Connection
Discharge Pressure
Valve
(shown backseated)