Tech Self Help Articles » Gen 3 Repairs » Gen 3: Replace Valves in Bellows Pump

Gen 3: Replace Valves in Bellows Pump

The bellows pump is the black and blue component mounted to a bracket on the left back wall of the unit.

Time:  15 minutes

  • Phillips head screwdriver (magnetized)
  • Zip tie snip and zip tie
  • paper towels for blotting concentrate
  • Pliers


  • Gen 3 Mini Bellows Pump Poppet Replacement Kit, #21270

Skip to valve replacement instructions.

1.  Remove bottle.  Reposition controller and shroud.  See Gen 3: Access Components by Repositioning Shroud.

2.  Remove bellows pump

C.  Disconnect bellows pump lead (brown, white wires, 2 pin connector) from wiring harness.

D.  Pull clear flexible tubing on the right (discharge) side of the bellows out of the batch tank.

E.  Snip zip tie securing dark flexible tubing to hose barb on coupler and pull tubing off the hose barb.  Use paper towels to blot any concentrate that may leak.

F.  The bellows pump frame is secured to bracket with two screws as shown.  Using magnetized Phillips head screwdriver, first remove screw nearest you.  Pull the pump slightly toward you, and then loosen the back screw (without removing it.).

G.  Slide bellows pump toward you and remove from unit.

3.  Replace poppet valves

A.  By hand or using pliers, unscrew hose connectors from pump head.

B. Remove one poppet valve and o-ring from each side of the pump head. You may have your screwdriver to push out the seal on the outlet side from the inlet side. Set aside.

C. Flex the new poppet valves by pulling the flat center disk away from the valve and letting is snap shut – see video above.

D. Insert the new poppets exactly the way the original set was oriented. Pay attention to direction of flow.

E. Replace hose connections on both sides of the pump.

4. Re-install bellows pump assembly

A.  Position new bellows pump on the bracket and slide it back so that the notch on the pump touches the back screw and then tighten the screw.  Secure the front of the pump frame to the bracket with the other screw.

B.  Slide the free end of the dark flexible tubing to the hose barb on the coupler and secure with zip tie.

C.  Push the clear flexible tubing on the right (discharge) side of the bellows pump into the grommet above the batch tank so that concentrate will pump into the batch tank.  DO NOT FORGET TO DO THIS!

D.  Connect the bellows pump lead (brown, white wires, 2 pin connector) to the wiring harness.

4.  Return shroud and controller to original position.

5.  Test bellows pump.

A.  Insert the insecticide bottle into the coupler and run a charge.

  • MAINTENANCE Menu, scroll to CHG.
  • Press and hold Green ► button for 3 seconds.
  • DOSE will flash for an extended period.

B.  While DOSE is flashing, lift the controller from its well in the shroud.  You should be able to see the white plastic bellows contracting and expanding.  After the pump primes, you should see be able to see the insecticide moving through the clear discharge tubing.