Lennox T-Class TSA H4 Series Installation Instructions Manual page 11

4
WRAP SERVICE VALVES
To help protect service valve seals during brazing, wrap a saturated cloth around service valve bodies and copper tube stub. Use another
saturated cloth underneath the valve body to protect the base paint.
5
FLOW NITROGEN
Flow regulated nitrogen (at 1 to 2 psig) through the refrigeration gauge set into the valve stem port connection on the liquid service valve and
out of the suction / vapor valve stem port. See steps 3A, 3B and 3C on manifold gauge set connections
6
BRAZE LINE SET
Wrap both service valves with a saturated cloth as illustrated here before brazing to line set.
Allow braze joint to cool. Apply
IMPORTANT —
additional saturated cloths to help cool brazed joint.
Do not remove wet rag until piping has cooled.
Temperatures above 250ºF will damage valve seals.
1. FIRE, PERSONAL INJURY, OR PROPERTY
DAMAGE will result if you do not wrap a wet cloth
around both liquid and suction line service valve
bodies and copper tube stub while brazing in the line
set! The braze, when complete, must be quenched
with water to absorb any residual heat.
2. Do not open service valves until refrigerant lines and
indoor coil have been leak-tested and evacuated.
Refer to procedures provided in this supplement.
7
PREPARATION FOR NEXT STEP
After all connections have been brazed, disconnect manifold gauge set from service ports. Apply saturated rags to both services valves to cool
piping. Once piping is cool, remove all wet cloths. Refer to the unit installation instructions for the next step in preparing the unit.
WHEN BRAZING LINE SET TO
SERVICE VALVES, POINT FLAME
AWAY FROM SERVICE VALVE.
WARNING
SUCTION / VAPOR LINE
Figure 9. Brazing Procedures (continued)
LIQUID LINE SERVICE VALVE
SUCTION / VAPOR LINE
SERVICE VALVE
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SATURATED CLOTH
LIQUID LINE
WHEN BRAZING LINE SET TO
SERVICE VALVES, POINT FLAME
AWAY FROM SERVICE VALVE.
SATURATED CLOTH
TSA*H4 SERIES