Tech-Note – Troubleshooting Internal Leaks – Type 2Valves
Troubleshooting
Internal Leaks
At the factory a baseline leak test is performed to verify leak-tightness and functionality. This test is a good indicator of an internal leak. The parameters are listed below.
When setting the test pressure, cap the test port before selecting the pressure field.
Running a capped port test with these parameters should yield a decay value less than 0.005psig.
Higher pressure range machines have a similar test with slightly longer fill times.
Valve manifold (removed from machine for clarity, removal of manifold is not necessary for cleaning or inspection)
The most common place for leaks to occur is at the junction of the test port fitting to the valve manifold.
When the test pressure is vented, the airflow path is through Valve 1 (on) and out to atmosphere through
Valve 2 (off).
Debris from test parts or dirty air can be trapped under the piston of the 2-Way valve, holding the valve in
an open position.
To clean debris from the valves, remove both cylinder head screws. The cylinder head and manifold body will separate. Check and clean for debris on both the valve seat and piston seal face.
To re-assemble verify the manifold body o-rings are in place, replace the cylinder head on the manifold, (pins will aid in alignment). Tighten the cylinder head screws, making sure not to over tighten or strip the screw. The cylinder head should be flush to the manifold body.
