GA FIGURE 942 User manual

Manual Number 942.1-IOM-110320
INSTALLATION, OPERATION AND
MAINTENANCE MANUAL
FIGURE 942
2”x1”, 2”and 3”x 2”Drawing ECAV-7104
COMBINATION AIR VALVES
FOR SEWAGE & WASTEWATER
TABLE OF CONTENTS
Introduction ….………………………… 2
Description of Operation .....………… 2
Receiving & Storage .....……………… 2
Installation ......…………………………. 2
Valve Construction ......………………. 3
Preventive Maintenance ....………….. 3
Trouble Shooting ...…………………… 3
Disassembly ....………………………… 3
Reassembly ....…………………………. 4
Backflushing Instructions …………… 4
Figure 942 Drawing/Parts List …….…. 5
How to Order Replacement Parts ..….. 5
Repair Kits ……………………………… 5
Warranty .……………………………….. 5
234 Clay Avenue • Mars, PA 16046 USA
Telephone [phone] • Fax [phone]
E-mail: [e-mail]

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INSTALLATION, OPERATION and
MAINTENANCE
Figure 942 Sewage Combination Air Valves
INTRODUCTION
This manual will provide the information to
properly install, operate and maintain the valve
to ensure a long service life. The GA Industries
Figure 942 Combination Air Valve is ruggedly
constructed to provide years of trouble-free
operation with minimal maintenance.
CAUTION
The valve is NOT recommended for use with
toxic fluids, fuels or fluids containing hazardous
gases
CAUTION
The valve will not function if used at a pressure
higher than the maximum working pressure
indicated on the nameplate.
The Shop Order (SO) Number, Figure Number,
size and pressure rating are stamped on a
nameplate attached to the valve. Please refer to
the SO number when ordering parts.
DESCRIPTION OF OPERATION
The Figure 942 Combination Air Valve is
designed to vent air through its large orifice as
the system is being filled with liquid and close
tight when the system is full and pressurized.
The valve automatically opens to admit air
through the large orifice during draining or when
the internal pressure falls below atmospheric.
The valve also releases air and sewage gas that
has accumulated within the valve while the
system is pressurized and operational.
These valves are usually installed at high points
in the system where air tends to collect and
vacuum conditions initially form during draining.
When empty of liquid, both the large and small
orifices are open allowing air to be vented ahead
of incoming liquid. The float rises when water
enters the valve and closes the orifices. As air
and sewage gas accumulate in the valve it
forces the water level down until the float drops
and opens the small air release orifice while the
large orifice remains closed. As air is released
the water level rises lifting the float and re-
closing the small orifice. This sequence occurs
as often as necessary to release air and gas that
has collected in the valve.
Should the pressure inside the valve fall below
atmospheric both the large and small orifices
open to allow air to be drawn into the system to
alleviate vacuum conditions.
RECEIVING AND STORAGE
Inspect the valve upon receipt for damage
during shipment. Carefully unload all valves to
the ground without dropping.
The valves should remain in a clean, dry and
weather protected area until installed. For long
term storage (greater than 6 months) the rubber
surfaces of the seat should be coated with a
non-toxic lubricant such as "SuperLube" made
by Synco Chemical. Do not expose the rubber
parts to sunlight or ozone.
INSTALLATION
The Figure 942 is standard with NPT screwed
pipeline connections up to 3”pipeline connection
size.
Consult the drawings of record to verify the
configuration supplied and installed.
The valve must be installed in an upright vertical
orientation, normally at a high point in the
system.
If installed outdoors, below ground in a vault or
in an unheated area, adequate freeze protection
must be provided.
An isolating valve should be installed between
the valve and the pipeline or system to facilitate
maintenance (included with backflushing
attachments).
Carefully screw threaded end valves onto pipe
nipple using compatible thread sealant. Tighten

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valve using wrench flats. DO NOT OVER-
TIGHTEN.
Flat-faced flanged valves should be mated with
flat-faced flanges and full-face gaskets. If ring
gaskets are used the bolt material shall be
ASTM A307 Grade B (or equivalent). Higher
strength bolting should only be used with full-
face gaskets.
Lower heavy valves over the mating flange
using slings or chains around the valve body.
Lubricate the bolts or studs and insert around
flange. Lightly tighten bolts until gaps are
eliminated. Torque bolts in an alternating
pattern in graduated steps. If leakage occurs
wait 24 hours and re-torque the bolts but do not
compress the gasket more than 50% or exceed
bolt maximum torque rating.
VALVE CONSTRUCTION
The standard Figure 942 Sewage Combination
Air Valve has a cast iron body, 316 stainless
steel float and linkage mechanism and a Buna-N
rubber seat. It has a working pressure range of
10 to 150 PSI. Optional materials can be
provided for higher working pressures. Refer to
the List of Materials submitted for the order if
non-standard materials were provided.
Refer to Page 5 for details of construction and
parts location.
The valve has an inlet connection at the bottom
where the valve attaches to the system and an
outlet connection at the top through which air
exits and enters the valve.
WARNING
Removing the valve from the line or
disassembling the valve while there is pressure
in the valve body may result in injury or damage
to the valve
PREVENTIVE MAINTENANCE
Figure 942 Sewage Combination Air Valves
require no scheduled lubrication or adjustment.
A periodic visual inspection should be performed
to ensure the outlet piping is not obstructed and
to verify there is no fluid leakage.
Depending on the nature of the fluid, sewage air
valves may become clogged with sediment or
grease and require periodic cleaning. To
facilitate such cleaning GA Industries air valves
with an “F” at the end of the Figure Number
(e.g., 942F) were supplied with “backflushing
attachments.” Refer to the backflushing
instructions on Page 4 of this manual for
additional information.
TESTING
Valve operation can be easily tested. Close the
inlet isolation valve and remove or loosen the
pipe plug nearest the inlet to drain the water
from the valve. The float should drop as the
water leaves the valve. NOTE: A manual valve
can be installed in place of the pipe plug to
facilitate testing (valves are included with
backflushing attachments).
Replace or tighten the pipe plug and slowly open
the inlet isolating valve. After expelling air, the
valve should close and seal tightly.
TROUBLESHOOTING
•Valve Does Not Close / Fluid Leakage
Verify there is at least 10 PSI at the valve
inlet for tight sealing
Verify debris has not collected on the seat
preventing tight closure
Verify rubber small and/or large orifice
seating surfaces are not damaged
Verify float has buoyancy
Verify linkage mechanism operates freely
without binding or sticking
•Valve Does Not Open
Verify debris in the valve is not
preventing the float from freely falling
when fluid is drained from valve
Verify linkage mechanism operates freely
without binding or sticking
Verify pressure at valve inlet does not
exceed 150 PSI
DISASSEMBLY
While small valves may be more easily serviced
by removing it from the line, all valves can be
serviced while the body remains connected to
the pipeline. A skilled technician with proper
tools should perform all work. No special tools
are required.
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4
Disassemble the valve only as far as needed to
replace damaged or worn parts.
First ensure there is no pressure within the
valve. Refer to Page 5 for parts location and
identification.
Remove the cover bolts (13) and lift off cover (2)
with float and linkage attached. It may be
necessary to pry the cover off. Be careful not to
damage or lose the cover O-ring (14) unless
being replaced.
Remove the spring pin (21) connecting the lever
arm to the cage (3). Remove the seat (4) from
the cage and remove the plug (5). Remove the
cage O-ring (16) and renewable seat (15) from
the seat. Remove bushing (6) from the cage.
Note: bushing only used in older valves with
ductile iron cage.
The float ball (12) is secured to the float rod (10)
by Loctite 263 and the hex nut (20). Loosen the
hex nut (20) and apply heat (approx. 550F) to
the connection while unscrewing the float ball by
hand. (If replacing the float ball, it may be more
practical to replace both the float ball and the
float rod.) Be careful not to lose the lock washer
(24).
The float hood (11) is attached to the float ball
(12) by a nylon cap screw (25) and lock washer
(24). The cap screw is secured by Loctite 380.
Inspect all parts for wear and damage. Minor
scratches and dents in the float are normal.
Replace the float if water is detected inside of it.
Replace damaged parts.
REASSEMBLY
Clean all parts especially seating and sealing
surfaces before reassembling valve. Worn parts
should be replaced during re-assembly.
Install bushing (6) and plug (5) in seat (4),
lubricate and install cage O-ring (16) and
renewable seat (15) in seat (4). Thread cage (3)
(with bushing), plug and seat into cover (2) and
tighten.
Thread orifice button (8) all the way into lever
arm (7) and install hex nut (22) and lock washer
(23) but do not tighten. Connect the lever arm
(7) to the cage (3) using spring pin (21).
Adjust the orifice button (8) so that the lever arm
(7) is parallel to the cover (2) when it is gently
resting on the plug (5) in the closed position.
Secure by tightening hex nut (8).
Install hex nut (20) and lock washer (24) onto
end of float rod (10). Apply Loctite 263 to the
threads on the float rod (10) and screw float ball
(12) onto float rod (10). Tighten hex nut (20).
Install lock washer (24) onto cap screw (25).
Apply Loctite 380 to cap screw (25) insert
through center hole in float hood, screw onto
float ball (12) and tighten.
Verify free movement of linkage mechanism and
that the orifice button (8) presses against the
plug (5) when it is closed and pulls away from
the plug when it in the fully open position.
Lubricate and place O-ring (14) in cover (2) and
carefully place cover (2) on body (1) ensuring O-
ring is retained. Install the cover bolts (13) and
tighten in an alternating pattern.
Carefully introduce pressure and check for
leaks.
BACKFLUSHING INSTRUCTIONS
Follow all local cross-connection and safety
codes and regulations!
To determine if a GA Industries sewage air valve
needs cleaning or backflushing:
•Close the inlet isolating valve then slowly
open the ½” flushing ball valve (if installed)
or slowly remove the pipe plug at the top
of air valve to relieve internal pressure.
•Open the 1” blow off ball valve (if installed)
or remove the pipe plug near the bottom.
Liquid should freely drain from the valve
body. If it does not, then the valve is likely
in need of cleaning or backflushing.
To clean a GA Industries sewage air release
valve equipped with backflushing attachments:
•Close the inlet isolating valve and then
slowly open the ½” flushing valve to
relieve internal pressure.
•Open the 1” blow off valve
•Connect the ½” flushing valve to a
pressurized source of clean water using
the rubber hose provided with the
backflushing attachments.

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•Introduce flushing water until liquid runs
freely from the blow off valve.
•Shut off and disconnect the supply of
clean water and close the blow off and
flushing valves.
•Slowly open the inlet isolating valve. The
air release valve should exhaust air and
then close tightly
REPLACEMENT PARTS
Genuine replacement parts are available from
your local VAG/GA Industries representative or
from the factory:
VAG USA, LLC
234 Clay Avenue
Mars, PA 16046 USA
Telephone: [phone]
Fax: [phone]
E-mail: [e-mail]
Please have the nameplate data available when
ordering parts
2”x 1”, 2”and 3”x 2”
FIGURE 942 PARTS LIST
Item Description Standard Material
1. Body Cast Iron
2. Cover Cast Iron
3. Cage 316 SS*
4. Seat 316 SS
5. Plug 316 SS
6. Bushing 316 SS*
7. Lever Arm 316 SS
8. Orifice Button Buna-N/SS
9. Universal Coupling 316 SS
10. Float Rod 316 SS
11. Float Hood 316 SS
12. Float Ball 316 SS
13. Cover Bolt Zinc Plated Steel
14. Cover O-Ring Buna-N Rubber
15. Renewable Seat Buna-N Rubber
16. Cage O-Ring Buna-N Rubber
17. ½” Pipe Plug Steel
18. 1” Pipe Plug Cast Iron
19. 2” Pipe Plug Cast Iron
20. Hex Nut 304 SS
21. Spring Pin 302 SS
22. Hex Nut 304 SS
23. Lock Washer 410 SS
24. Lock Washer 410 SS
25. Cap Screw Nylon
*Older valves have
cast iron cage with
bushing. Bushing
not used with 316S
cage.
REPAIR KITS
Soft Goods Kit A942-2 (Part Number 2-80-
11000-024) includes Items 8, 14, 15, 16, 22 &
23
Linkage Kit AL942-2 (Part Number 2-80-11000-
092) includes Items 7, 9, 10, 20, 21, 22, 24 and
25
All other parts ordered individually.
WARRANTY
The Warranty for GA Industries valves is
included in our Terms and Conditions which can
be found here: https://gaindustries.com/terms