Figure 7.3 Service Valve - Carrier 69NT40-561-019 Operation And Service Manual

1. Line Connection
2. Access Valve
3. Stem Cap
4. Valve stem
To connect the manifold gauge/hose set for reading pressures, do the following:
a. Remove service valve stem cap and check to make sure it is backseated. Remove access valve cap.
(Figure 7.3).
b. Connect the field service coupling (see
c. Turn the field service coupling knob clockwise, which will open the system to the gauge set.
d. To read system pressures, slightly midseat the service valve.
e. Repeat the procedure to connect the other side of the gauge set.
To prevent trapping liquid refrigerant in the manifold gauge set be sure set is brought to suc-
tion pressure before disconnecting.
Removing the Manifold Gauge Set:
a. While the compressor is still ON, backseat the high side service valve.
b. Midseat both hand valves on the manifold gauge set and allow the pressure in the manifold gauge set to be
drawn down to low side pressure. This returns any liquid that may be in the high side hose to the system.
c. Backseat the low side service valve. Backseat both field service couplings and frontseat both manifold
hand valves. Remove the couplings from the access valves.
d. Install both service valve stem caps and service port caps (finger-tight only).

Figure 7.3 Service Valve

1
6
5
Figure
CAUTION
!
2
4
5. Compressor Or Filter Drier Inlet
Connection
6. Valve (Frontseated)
7. Valve (Backseated)
- - - - -
7.2) to the access valve.
7–3
3
7
T-359