TM9-4120-400-14
Table 3-1.
Operator Troubleshooting - continued
MALFUNCTION
TEST OR INSPECTION
C O R R E C T I V E ACTION
Step 6. Check if EVAPORATOR FAN SPEED switch is set at LOW speed.
Set switch to HIGH speed.
Step 7. Check that condenser air inlet guard or discharge air louver are not obstructed.
Remove obstruction.
Step 8. Check condition of refrigerant in sight glass.
If refrigerant color is in the yellow zone or numerous bubbles appear in window, turn selector
to OFF and contact direct support maintenance.
3. REDUCED HEATING
CAPACITY.
Step 1. See that MODE SELECTOR switch is properly set.
Set switch on LOW or HIGH HEAT.
Step 2. Check operation of TEMPERATURE SELECTOR switch.
Set control to fully WARMER then, if condition improves, adjust properly.
Step 3. Check that supply and return air louvers are properly adjusted.
Adjust louvers to open position.
Step 4. Check that excessive cold, outside air is not being introduced through fresh air damper.
Fully close damper, then, if condition improves, adjust properly.
Step 5. Check that all doors, windows, and other openings in room or enclosure are tightly closed.
Tightly close all openings.
Step 1. See that MODE SELECTOR switch is properly set.
Set switch on LOW HEAT. (When MODE SELECTOR switch is set for HIGH HEAT, half of
the heaters will operate all of the time.)
Step 2. Check operation of TEMPERATURE SELECTOR switch.
Adjust to a slightly COOLER setting.
3-3