SERVICE
NOTE: The following steps should be performed by a quali- ®ed service person.
WARNING: Before installing or servicing unit, turn off main power to system to avoid shock hazard or in- jury from rotating parts. There may be more than one disconnect switch. Turn off accessory heater power if applicable. Electrical shock can cause personal injury or death.
I. CLEANING
Inspect unit interior at the beginning of each heating and cool- ing season or as operating conditions require. To inspect and clean, the unit top must be removed.
A. Unit Top Removal
NOTE: When performing maintenance or service procedures that require removal of the unit top, be sure to perform all of the routine maintenance procedures that require top re- moval, including: coil inspection and cleaning, and conden- sate drain pan inspection and cleaning.
Only quali®ed service personnel should perform mainte- nance and service procedures that require unit top removal. Refer to the following top removal procedures:
1.Remove 7 screws on unit top cover surface. Save all screws.
2.Remove 2 screws that secure unit top cover ¯ange. Save all screws.
3.Lift top from unit carefully. Set top on edge and ensure that top is supported by unit side that is opposite duct side.
When maintenance and/or service procedures are concluded, carefully replace and secure unit top to unit, using screws re- moved in Steps 1 and 2.
B. Repairing Refrigerant Leaks
Proceed as follows to repair a refrigerant leak and to charge the unit.
1.Locate leak and ensure that refrigerant system pres- sure has been relieved and recovered from both high- and
2.Repair leak following accepted practices.
NOTE: Install a ®lter drier whenever the system has been opened for repair.
3.Add a small charge of nitrogen vapor to system and leak- test unit.
4.Evacuate refrigerant system if additional leaks are not found.
5.Charge unit with
NOTE: See Adjusting Refrigerant Charge on page 16.
C.Condenser Coil, Evaporator Coil, and Condensate Drain Pan
WARNING: Be careful! Coil ®ns are sharp. Protect hands with gloves when cleaning or handling coil.
Inspect the condenser coil, evaporator coil, and condensate drain pan at least once each year. Proper inspection and clean- ing requires the removal of the unit top. See Unit Top Removal section above.
The coils are easily cleaned when dry; therefore, inspect and clean the coils either before or after each cooling season. Remove all obstructions (including weeds and shrubs) that interfere with the air¯ow through the condenser coil. Straighten bent ®ns with a ®n comb. If coated with dirt or lint, clean the coils with a vacuum cleaner, using a soft brush attachment. Be careful not to bend the ®ns. If coated with oil or grease, clean the coils with a mild
Inspect the drain pan and condensate drain line when inspecting the coils. Clean the drain pan and condensate drain by removing all foreign matter from the pan. Flush the pan and drain tube with clear water. Do not splash water on the insulation, motor, wiring, or air ®lter(s). If the drain tube is restricted, clear it with a ``plumbers snake'' or similar probe device. Ensure that the auxiliary drain port above the drain tube is also clear.
II. EVAPORATOR FAN AND MOTOR
Refer to Care and Maintenance section for procedure.
III. CONDENSER FAN
CAUTION: Keep the condenser fan free from all obstructions to ensure proper cooling operation. Never place articles on top of the unit. Damage to unit may result.
1.Shut off unit power supply.
2.Remove
3.Loosen fan hub setscrews.
4.Adjust fan height as shown in Fig. 18.
5.Tighten setscrews.
6.Replace
Fig. 18 Ð Condenser-Fan Adjustment
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