Desa BTU/HR - Manual (Page 14)

www.desatech.com 113282-01C 14
SERVICE PROCEDURES
Continued
PUMP ROTOR
(Procedure if Rotor is Binding)
1. Remove upper shell (see Upper Shell Re-
moval, page 9).
2. Remove filter end cover screws using 5/16"
nut driver (see Figure 30 or 31).
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 (see Figure
30 or 31).
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 Figure 32).
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 (see Upper
Shell Removal, page 9).
12. Adjust pump pressure (see Pump Pressure
Adjustment, page 10).
Note:
If rotor is still binding, proceed as
follows.
13. Perform steps 1 through 6.
14. Place fine grade sandpaper (600 grit) on flat
surface. Sand rotor lightly in “figure 8” mo-
tion four times (see Figure 33).
15. Reinstall insert and rotor.
16. Perform steps 10 through 12.
Figure 30 - Rotor Location, 40/50/55/60/
70 Models
Pump
Plate
Insert
Rotor
Blade
Filter
End
Cover
Air Intake
Filter
Air Output Filter
Figure 31 - Rotor Location, 110/115/155/
165/200 Models
Insert
Blade
Rotor
Pump Plate
Air
Intake
Filter
Air Output Filter
Filter End Cover
Gap Adjusting Screw
Rotor
Blade
.003"/.004"
(.076-.101 mm)
Gap Measured
With Feeler
Gauge
Gap Adjusting Screw
Figure 32 - Gap Adjusting Screw Locations
Sandpaper
Figure 33 - Sanding Rotor