Installation
Troubleshooting Air Valves (AST4, AST4-F)
Turn off water supplies to the
unit before troubleshooting.
Item
Qty.
1
1
Diaphragm
2
1
Armature
3
1
Spring
4
1
AST 4 Valve Upper Body
5
1
Magnet/Diaphragm Assembly
6
1
AST 4 Valve Cover
7
1
AST 4 Valve Clamp Nut
8
1
AST 4 Valve Timer Assembly
9
2
O-Ring
10
1
AST 4 Valve Timer Cover
11
1
Compression Nut, 1/8" Tube
12
3
Screw, #8 x 7/8"
13
1
Compression Nut, 1/4" Tube
14
1
Tube Connector 10-32 x 1/8"
Problem
Valve will not shut
Timing mechanism is
off .
clogged .
One or more
Water is not being
individual operating
supplied to unit .
stations fail to turn
Water pressure is
on .
over 80 PSI .
Failed diaphragm/
magnet assembly .
One or more
There is an air leak .
individual operating
stations turn off too
quickly or run too
long .
Pushbutton does
Air volume may
not work properly .
not be sufficient to
operate valve .
Water is dripping
Debris has
from the
accumulated on
streamformers .
valve seat or orifices .
Bradley • 215-1068 Rev. J; ECN 14-00-007
Description
Cause
Clean and inspect timing mechanism:
1 . If compressed air is available, blow water and debris from timer cover of timing
mechanism .
2 . Turn adjusting screw out all the way . Clean and inspect screw and valve body .
3 . Turn adjusting screw in to desired cycle time .
Open all stops on mixing valve .
Install a pressure reducing valve .
Unscrew the valve clamp nut on valve . Remove valve cover . Gently press the
diaphragm . The valve should activate . If not, replace the diaphragm/magnet assembly .
Check the valve assembly:
1 . Check all tubing and fittings for proper assembly .
2 . Tighten cap and nut on 1/8" tubing .
Check for leaks and lubricate U-cup:
1 . Check all fittings for air leaks .
2 . Disassemble pushbutton and lubricate U-cup seal (see pushbutton assembly
diagram on next page) .
Clean and inspect valve seat:
1 . Remove screws and disassemble metering valve .
2 . Clean valve seat and inspect for deep gouges or scratches . Replace valve body
if necessary .
3 . Remove any debris clogging off-center hole in rubber diaphragm .
AST4-Hand Valve Only
11
10
9
8
9
AST4-Hand Valve, AST4-F Foot Valve
Solution
SN2008/AST4, SN2008/AST4-F
AST4-F Foot Valve Only
14
7
6
5
12
3
4
1
2
13
8/18/2014
9