Piper SARATOGA PA-32-301 Maintenance Manual page 125

COMPOUND
PRESSURE GAGE
C
SERVICE VALVE
Figure 21-5. Test Gauge and Manifold Set
TEST GAUGE AND MANIFOLD SET.
The proper testing and diagnosis of the air conditioning system require that a manifold gauge set be
attached into the system. This set consists of two gauges mounted to a manifold. One gauge is a high pressure
gauge used in the discharge side of the system. The other is a low pressure gauge used in the suction side of the
system. The manifold is a device having fittings for both gauges and connection hoses with provisions for
controlling the flow of refrigerant through the manifold. (See Figures 21-5 and 21-6.)
The center port of the manifold set is used for charging or evacuation procedures. or any other ser ice that
may be necessary.
Both the high and low side of the manifold have hand shut-off valves. When the hand valve is turned all
the way in. in a clockwise direction. the manifold is closed. The pressures on that side of the system will.
howeer. be recorded on the gauge above the hose.
Cracking the hand valve. in the counterclockwise direction, opens the system to the middle service port of
the manifold set This is desirable only when it is necessary to let refrigerant out or into the system. Refer to
Figures 21-5 or 21-6.
CHECKING THE SYSTEM FOR LEAKS.
There are several methods of doing this operation. depending on the type of equipment which is available.
Two methods of performing this check will be covered in the following paragraphs.
21-54-00
Page 21-19
Revised: August 11. 1983
1F5
PIPER AIRCRAFT
PA-32-301/301T
MAINTENANCE MANUAL
408
HIGH PRESSURE
GAGE
TO DISCHARGE
SERVICE VALVE
TO VACUUM PUMP OR
REFRIGERANT CYLINDER