Sentry
™
Washfountain
Parts and Service Guide
26
Bradley Corporation • 215-1472 Rev. F; EN 06-915
2/12/07
Troubleshooting Air Valve Metering Hand Control (AST4)
CAUTION: Turn off water supplies to unit before troubleshooting.
Problem:
One or more individual operating stations fail to turn on.
Cause:
Incoming water pressure is over 80 PSIG.
Solution:
Reduce water pressure to below 80 PSIG.
Install a pressure-reducing valve at the building main set to the manufacturer's recommendations.
Lower line pressure will improve the performance and extend the life of all the plumbing in the
building.
Problem:
An individual operating station fails to turn on.
Cause:
A failed diaphragm/magnet assembly.
Solution:
Test the station to determine cause.
1. Unscrew the valve clamp nut on the top of the valve (see Page 25).
2. Remove valve cover. If the diaphragm/magnet assembly comes out with the cover, gently peel
the diaphragm away form the cover, taking care not to damage the diaphragm. Inspect the
diaphragm for any holes of tears. A damaged diaphragm needs to be replaced.
3. Insert the diaphragm/magnet assembly back into the valve, but leave the cover off.
4. Gently press the diaphragm until it is fully depressed. The valve should activate. If not, the
diaphragm/magnet assembly needs to be replaced.
Problem:
One or more individual operating stations turn off too quickly or run too long.
Cause:
Timing requires adjustment.
Solution:
Readjust timing (see Page 24).
Problem:
An individual operating station cannot be adjusted to run for more than five seconds.
Cause:
Air tube connection leak.
Solution:
Check 1/8" tubing connection.
1. Tighten compression nut at 1/8" tubing connection to air valve in pedestal.
2. If leak persists, remove the sprayhead cover and check the 1/8" elbow tube connection behind
the pushbutton assembly. Make sure the screw holding the elbow is tight and the fitting in the
elbow is firmly hand tightened. Make sure the tubing is pushed firmly into the fitting.
3. If leak persists, reseat the 1/8" tubing. Disconnect the tubing from the fitting by pressing down
on the plastic ring at the top of the fitting while firmly pulling the tubing out of the fitting. Trim
½" off the end of the tubing squarely with a razor-sharp knife and push the tubing firmly back
into the connector to make sure it is seated.
4. If the leak still persists, loosen the compression nut on the air valve inside the pedestal and pull
the tubing out of the fitting. Trim ½" off the end of the tubing squarely, with a razor-sharp knife.
Then slide the tubing through the nut until ½" of tubing is exposed. Insert tubing into the com-
pression fitting on the valve body and hand tighten the compression nut.
