Pump Rotor - Desa D20N Owner's Manual

D20N, D30N AND D44N MODELS
PORTABLE FORCED AIR HEATERS
SERVICE
PROCEDURES
Continued

PUMP ROTOR

(Procedure if Rotor is Binding)
1. Remove upper shell (see page 8).
2. Remove filter end cover screws using
5/16" nut-driver.
3. Remove filter end cover and air filters.
4. Remove pump plate screws using 5/16"
nut-driver.
5. Remove pump plate.
6. Remove rotor, insert, and blades.
7. Check for debris in pump. If debris is
found, blow out with compressed air.
8. Install insert and rotor.
9. Check gap on rotor. Adjust to .076/.101
mm (.003"/.004") if needed (see Fig-
ure 25).
Note: Rotate rotor one full turn to ensure
the gap is .076/.101 mm (.003"/.004") at
tightest position. Adjust if needed.
10. Install blades, pump plate, air filters,
and filter end cover.
11. Replace fan guard and upper shell.
12. Adjust pump pressure (see page 10).
Note: If rotor is still binding, proceed as
follows.
13. Perform steps 1 through 6 above.
14. Place fine grade sandpaper (600 grit)
on flat surface. Sand rotor lightly in
"figure 8" motion four times (see Fig-
ure 26).
15. Reinstall insert and rotor.
16. Perform steps 10 through 12 above.
Insert
Figure 23 - Rotor Location, D20N Model
Insert
Rotor
Air Output
Filter
Figure 24 - Rotor Location, D30N and D44N Models
Gap Adjusting
Screw
Blade
Gap Adjusting
Screw
Figure 25 - Gap Adjusting Screw Locations
12
Blade
Pump
Plate
Rotor
Air Output
Filter
Blade
Pump
Plate
.076/.101 mm (.003"/.004") Gap
Measured With Feeler Gauge
Rotor
Sandpaper
Figure 26 - Sanding Rotor
Air
Intake
Filter
Filter End
Cover
Fan Guard
Air Intake Filter
Filter End
Cover
Fan Guard
105843