Service; Section Layout; Service Valves; Figure 7.1 Service Valve - Carrier 69NT40-541-001 Operation And Service

To avoid damage to the earth's ozone layer, 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.
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.
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
Contents to locate specific topics.
7.2

SERVICE VALVES

The compressor suction, compressor discharge and liquid line service valves (see
double seat and a gauge connection which enable servicing of the compressor and refrigerant lines. Turning the
valve stem clockwise (all the way forward) will frontseat the valve to close off the suction, discharge or liquid line
and open the gauge port to the compressor or low side. Turning the stem counterclockwise (all the way out) will
backseat the valve to open the connections and close off the port
With the valve stem midway between frontseat and backseat, the lines are open to both the connections and the
gauge connection.
For example, the valve stem is first fully backseated when connecting a manifold gauge to measure pressure.
Then, the valve is opened 1/4 to 1/2 turn to measure the pressure.
1
1. Suction, Discharge or Liquid Line Connection
2. Service Port
3. Stem Cap
SECTION 7

SERVICE

NOTE
WARNING
!

Figure 7.1 Service Valve

VALVE
FRONTSEATED
(Clockwise)
2
VALVE
5
BACKSEATED
(Counterclockwise)
4. Valve Stem
5. Compressor or Filter Drier Inlet Connection
- - - - -
7–1
Table of
Figure 7.1) are provided with a
3
4
T-316