DirectFlo DF1400
Chapter 5: Trouble-Shooting and Repair
Comco Inc.
5-12
Issue Date: January 2009
Vent Pinch Tube and Plunger Inspection
1.
Turn off and unplug the DirectFlo.
2.
Use a 7/16” wrench to remove the connector nut on the vent hose fitting
on the rear panel. Remove the hose and pull it through the pinch tube.
3.
Remove the pinch tube. Inspect it for sharp edges or pitting due to
abrasive leakage. Replace if necessary with Comco part number
MB1282.
4.
Inspect the pinch plunger for sharp edges or pitting due to abrasive
leakage. Replace if necessary with Comco part number MB1050-2.
5.
Inspect the piston rod by pulling it out about 1/2”. It should be clean, dry
(not oily), and n
ot “gritty”. Wipe thoroughly. The rod should retract easily
when released.
6.
Install the pinch tube. The pinch tube should be hand tightened all the
way onto the cylinder and then backed off about 1/4 turn until the hole is
horizontal.
7.
Install the hose - see procedure, above.
Replacing the Vent Pinch Assembly
(refer to Appendix B, Figure 9)
Prior to replacing the assembly check for proper pinch cylinder operation by performing
the “Set-up and Test Procedure” in Chapter 2 beginning with step 14. If any problems
are encountered, verify at least 80 psi is supplied to the cylinder from the air source
when the unit is turned ON. And the pressure to the cylinder drops to 0 psi when the
unit is turned OFF.
If the vent hose pinch will not close to stop the flow of air, or open to allow the venting of
the DirectFlo, the pinch assembly will need to be replaced. Follow the procedure below,
“Vent Pinch Assembly Replacement”.
Vent Pinch Assembly Replacement Procedure (PF2445)
1.
Turn off and unplug the DirectFlo.
2.
Remove the tank enclosure gasket and cabinet cover. See instructions
above.
3.
If not already removed, remove the pinch tube from the pinch.
4.
Disconnect the air hose from the rear of the cylinder.
5.
With a 7/8” wrench remove the cylinder mounting nut. Pull cylinder out
from inside the unit.
6.
Reverse procedure to install new cylinder assembly (PF2445).
7.
Replace the cover.