Operating Service Valves - Lennox MS8 SERIES Installation And Service Procedures

Operating Service Valves

The large line service valve on the outdoor unit is used to
purge air, test for leaks, check operating pressures and add
refrigerant to system. The 3-way service valve is equipped
with a service port which has a factory-installed valve core.
Figure 32 provides information on how to access and
operate the 3-way service and 2-way shut-off valves.
IMPORTANT
To prevent stripping of the various caps, use an
appropriately sized wrench and fit the wrench snugly over
the cap before tightening.
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Corp. 1244-L9