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(3) EvapFM Diagnosis
UR/WR: EvapFM continues. If not, check for 115VAC at CM
AUX 1 black-smooth (BK-SM) wire to a neutral white (W). If 115VAC is not
present, replace CM.
SR and UF/WF: Confirm EvapFM de-energizes. If not, check for 115VAC at
CM AUX 1 black-smooth (BK-SM) to a neutral white (W). If 115VAC is present,
confirm Comp and ConFM de-energized. Next, check DTh continuity. See "II.D.
Thermistor Check." Replace as needed. If DTh confirmed, replace CM.
(4) DH Diagnosis (SR and UF/WF): Confirm DH energizes. Check for 115VAC at
CM AUX 2 black (BK) wire to a neutral white (W). If 115VAC is present, confirm
Comp, ConFM, and EvapFM de-energized. Next, check DTh continuity. See "II.D.
Thermistor Check." Replace as needed. If DTh confirmed, replace CM.
2) Defrost Termination
Manually Terminated Defrost: Set the CTCD to the off position, then back to
original setting or unplugging and plugging back in to the electrical outlet. Defrost
terminated. If not, replace CM.
Temperature/Time Terminated Defrost
a) UR/WR: DTh warms to 45°F (7.2°C). Confirm continuity of DTh.
See "II.D. Thermistor Check." Replace as needed. If DTh confirmed, replace CM.
Once defrost termination achieved, EvapFM continues. Comp and ConFM energize.
If not, see "4) Startup/Cool down" above.
b) SR: DTh warms to 46°F (7.7°C). DH de-energizes. Confirm continuity of DTh. See
"II.D. Thermistor Check." Replace as needed. If DTh is good and DH continues after
DTh achieves 46°F (7.7°C), replace CM. Comp, ConFM, and EvapFM energize. If
not, see "4) Startup/Cool down" above.
c) UF/WF: DTh warms to 55°F (12.7°C) DH de-energizes. Confirm continuity of DTh.
See "II.D. Thermistor Check." Replace as needed. If DTh is good and DH continues
after DTh achieves 55°F (12.7°C), replace CM. 3-min. DOT starts. 3-min. DOT
terminates. If CTh calling for cooling, Comp, ConFM, PH, and MH energize. Once
evaporator temperature achieves 10°F (-12.2°C) or 3-min. EvapFM delay timer
terminates, EvapFM energizes. If not, see "4) Startup/Cool down" above.
Legend: Comp–compressor; ConFM–condenser fan motor; CLS–cabinet light switch;
CM–control module; CTCD–cabinet temperature control dial; CTh–cabinet
thermistor; DH–defrost heater; DLT–defrost lock-out timer; DST–defrost safety
thermostat; DT–defrost timer; DTh–defrost thermistor; EvapFM–evaporator fan
motor; HPS–high-pressure switch; MH–mullion heater; PH–perimeter heater
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