The Importance of Maintaining your Solution Outlet Check Valve

Ara Klujian

Moderator & TMF Repair Expert
Premium VIP
Jun 19, 2008
Chicago, IL
Real Name
Business Location
United States
:hi:If you have a chemical pump with last stage chemical injection, then you have an outlet check valve. This check valve is located in a manifold or as Prochem calls a Y-Strainer manifold, which is near the water pumping system outlet quick disconnect. This is otherwise known as the solution outlet of your truckmount. The check valve itself is positioned so all the water leaving the machine passes through this and prevents any chemical from entering the water pumping system, prior to the manifold or Y-Strainer.

Inspecting this check valve regularly is an important part in maintaining a properly running chemical system. Ideally, the check valve should be inspected at least once a month or every 100 hrs of operation. Inspection should include checking spring and spring tension, teflon seat for wear, cracks within the check valve body and signs of wear with the o-rings.

Typical signs that your check valve and o-rings need replacement are:
  • Solution flowing when cleaning tool is off
  • Less sensitivity when adjusting flow rate
  • Abnormal flow rate (does not reach desired flow rate)
  • Soap in your water box
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New Member
Dec 1, 2011
Real Name
Tom Eifler
Business Location
United States
Thanks Ara, I was having the problem of my chemicals flowing even when I don't trigger the wand. Changing the check valve worked. I have a Panther 25 with last point chemical injector. Thanks again for the advice!