Cla-Val 36 Series - Manual (Page 2)

When the system is drained, the plug will reopen allowing air
to rapidly re-enter the piping system. See Figure 4. 3.
Figure 4. Air Enters
During Pipeline
Draining
INLET
At other times the valve is closed and under pressure as shown
in Figure 5.
Figure 5. Pipeline
Under Normal
Pressure
INLET
INSTALLATION
The installation of the valve is important for its proper operation.
Valves must be installed at the system high points in the vertical
position with the inlet down. For pipeline service, a vault with
freeze protection, adequate screened venting, and drainage
should be provided. During closure, some fluid discharge will
occur so vent lines should extended to an open drain area in
plant services. A shut-off valve should be installed below the
valve in the event servicing is required.
CAUTION: Installed valve with “INLET” port down or
leakage will occur.
MAINTENANCE
The Combination Air Valve requires no scheduled lubrication or
maintenance.
INSPECTION: Periodic inspection to verify operation can be per-
formed. A manual drain valve can be installed in the lower drain
plug to plug to perform this operation as shown in Figure 7.
FIGURE 7. INSPECTION PIPING
With the inlet shut-off valve open, partially open the drain
valve until flow can be heard. If the air valve is working prop-
erly, water should be exhausted from the drain valve. If air is
exhausted, follow steps 2-6. 1.
Close the inlet shut-off valve. 2.
Slowly open the drain valve to allow the fluid in the valve to
drain. If draining is difficult, the valve may be clogged (valve
requires service). 3.
Close the drain valve 4.
Slowly open the inlet shut-off valve to fill the valve with water.
Observe the seating action and verify that the valve closes
without leakage. 5.
If leakage occurs, the valve should be removed and inspect-
ed for water or possible damage from foreign matter. 6.