Val-Matic 6-8 Combination Air Valve (Single Housing Type) - Manual (Page 5)

4
MAINTENANCE
The Combination Valve requires no scheduled
lubrication or maintenance.
INSPECTION: Periodic inspection for leakage
can be performed. A manual drain valve can be
installed in the lower drain plug to perform this
operation as shown in figure 3.
1. With the inlet shutoff valve open,
partially open the drain valve until flow
can be heard. If the air valve is working
properly, water should be exhausted
from the drain valve. If air is exhausted,
follow steps 2-6.
2. Close the inlet shutoff valve.
3. Slowly open the drain valve to allow the
fluid in the valve to drain.
4. Close the drain valve.
5. Slowly open the inlet shutoff valve to fill
the valve with water. Observe the
seating action and verify that the valve
closes without leakage.
6. If leakage occurs, the valve should be
removed and inspected for wear or
possible damage from foreign matter.
Figure 3. Inspection Piping
TROUBLESHOOTING
Several problems and solutions are presented
below to assist you in troubleshooting the valve
assembly in an efficient manner.
1. Leakage at Bottom Connection: Tighten
valve flanged connection. If leak persists,
remove valve and replace gasket.
2. Leakage at Cover: Tighten bolts to 150
ft-lbs, replace gasket.
3. Valve Leaks when Closed: Flush valve to
remove debris. Disassemble and inspect
seats, orifice button and floats. NOTE:
Many floats contain sand for weight but if
water is detected, replace float.
4. Valve Not Venting Air: Check that
operating pressure does not exceed
Working Pressure on nameplate.
Perform inspection steps 2-6 and
disassemble valve if problem persists.
DISSASSEMBLY
The valve can be disassembled without
removing it from the pipeline. Or for
convenience, the valve can be removed from the
line. All work on the valve should be performed
by a skilled mechanic with proper tools. No
special tools are required.
1. Close inlet shutoff valve. Open drain
valve or remove drain plug. Remove
hood if needed. Remove the cover bolts
(7) on the top cover.
2. Pry cover (2) loose and lift off valve
body. Both float mechanisms will
remain attached to the cover.
3. Remove the retainer rings (13) and pivot
pins (12) that pass through the float arm
(10) and orifice button arm (22).
4. Remove retaining screws (8A) and lever
frame (3). Remove orifice (4A) from
cover (2).
5. Remove locknut (18) and orifice button
(11) from orifice button arm (22).
6. Remove retaining screws (8).
7. Lift float (5) from body (1). Remove
cushion (15) and guide bushings (9)
which are threaded into the body (1) and
cover (2).
8. Clean and inspect all parts. Note: Some
floats contain sand for extra weight; if
water is detected, replace float.
Replace worn parts as necessary and
lubricate parts with FDA grease.
Remove all foreign matter from body
and cover.
WARNING: The valve must be drained
before removing the cover
or pressure may be
released causing injury.