Operating instructions

TM 11574A-OI
3-56
(2) Refrigeration System.
Step Probable Cause Remedy
1 Shortage of refrigerant. Check refrigerant IAW 3-10b(2)(e).
Recharge refrigerant IAW 3-10b(4).
If fault is not corrected proceed to step 2.
2 Evaporator coil covered with ice. Refer to section 3-11d.
If fault is not corrected proceed to step 3.
3 Evaporator coil plugged with debris. Refer to section 3-10b(11).
If fault is not corrected proceed to step 4.
4 Evaporator fan(s) rotating backwards. Refer to section 3-10b(11)/3-10b(12).
If fault is not corrected proceed to step 5.
5 Defective evaporator fan motor/capacitor. Refer to section 3-10b(13).
If fault is not corrected proceed to step 6.
6 Air bypass around evaporator coil. Check for foreign air restrictions.
If fault is not corrected proceed to step 7.
7 Controller set too low. Reset.
If fault is not corrected proceed to step 8.
8 Compressor service valves or liquid line
shutoff valve partially closed.
Open valves completely.
If fault is not corrected proceed to step 9.
9 Dirty condenser. Refer to section 3-10b(7).
If fault is not corrected proceed to step 10.
10 Compressor worn. Refer to section 3-10b(5).
If fault is not corrected proceed to step 11.
11 Current limit (function code Cd32) set to
wrong value.
Refer to section 2-6e.
If fault is not corrected proceed to step 12.
12 Suction modulation valve malfunction. Refer to section 3-10b(14).
n. Unit runs but has insufficient cooling.
(1) Compressor.
Step Probable Cause Remedy
1 Compressor valves defective. Refer to section 3-10b(5).
If fault is not corrected proceed to c (2).