Graco Therm-O-Flow 55-H, Instructions-Parts List Manual

Page: 31 / 76

31 310–534
Heated Pump Troubleshooting
For more information about the Check-Mate 800 Displacement Pump, see Form# 308–570. For more information
about the Therm-O-Flow Pump Module, see Form# 310–530.
Problem Cause(s) Solution(s)
Rapid down stroke or up stroke
(pump cavitation) Material not heated to proper
pumping temperature. Check and adjust temperature set point.
(p p )
Air is trapped in pump. Bleed air from the pump using this pro-
cedure:
1. Place a waste container under the
pump bleed port.
2. Open the bleed port part way.
3. Turn on air to the pump
4. Allow material to flow from the bleed
port until it is air-free.
5. Shut off air to the pump and close
the bleed port.
6. Turn air on to the pump and set the
pump air regulator for normal opera-
tion.
Downstroke: Lower check in
pump is worn.
Upstroke: Upper check in pump is
worn.
Rebuild and replace pump, as neces-
sary.
Material leaks around pump outlet Outlet fitting is loose. Tighten outlet fitting.
Material leaks around bleed port Bleed port fitting is loose. Tighten bleed port fitting.
Pump won’t move up or down Problem with air motor. See Air Motor Troubleshooting chart on
page 32.
Foreign object lodged in pump. Remove object and rebuild pump
assembly.
WARNING
To reduce the risk of serious injury
whenever you are instructed to relieve
pressure, always follow the Pressure
Relief Procedure (page 20).
Before attempting to dislodge a foreign
object:
1. Relieve system pressure.
2. Remove the pump from the air
motor.
Wet-cup leaks Worn throat seal. Replace wet-cup and throat seal pack-
ings.