TM9-4120-398-14
TABLE 4-2. UNIT TROUBLESHOOTING-Continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
12.
REDUCED HEATING CAPACITY.
Step 1. Check for clogged air filter.
Clean air filter. (See paragraph 4-21.)
Step 2. Check for defective heater control relay (K7-K8).
Replace relay. (See paragraph 4-28.)
Step 3. Check for defective heating element.
Replace heating element, (See paragraph 4-35.)
Step 4. Check for defective thermostat (S2.)
Replace thermostat. (See paragraph 4-26.)
Step 5. Check for defective evaporator blower.
Replace blower. (See paragraph 432.)
Step 6. Check for defective high temperature cut out.
Replace high temperature cut out. (See paragraph 4-38.)
If problem still exists, refer to supervisor.
Section V. UNIT MAINTENANCE PROCEDURES
4-9. GENERAL.
The procedures in this section have been arranged in the order in which the items appear in the
organizational (O) maintenance level column on the Maintenance Allocation Chart (MAC) which is provided in Appendix B.
Step-by-step procedures have been provided for all actions authorized to be performed by Unit Maintenance in the order in
which they appear on the MAC.
The procedures in this section have been arranged in the order in which the items appear in the organizational (O) maintenance
level column on the Maintenance Allocation Chart (MAC) which is provided in Appendix B. Step-by-step procedures have
been provided for all actions authorized to be performed by Unit Maintenance in the order in which they appear on the MAC.
