18
2b)
Manually Initiated Defrost-Termination
: Has DTh warmed to 59°F (15°C)? If not
yet confirmed, confirm DTh status. See "II.D. Thermistor Check." If DTh is in proper
range, DH de-energizes and 2 delay timers start. If DTh has not warmed to 59°F
(15°C), check DT and DH continuity. Next, check DH amp draw.
(1)
3-min. Comp/ConFM and EvapFM delay timers terminate
: 3 min. after DH
de-energizes, confirm defrost icon turns off, Comp and EvapFM icons turn on,
and Comp, ConFM, and EvapFM energize. If not, confirm cabinet temperature is
warm enough for Comp and ConFM operation.
Comp and ConFM
: Check for 115VAC at CM C1 (R or V) to neutral (W).
If 115VAC is not present, check CTh status. See "II.D.Thermistor Check." If CTh
ohm reading is in proper range, replace CM. If 115VAC is present, check for
115VAC at CR #4 (BK) to neutral (W) and CR #6 (R) to neutral (W). If 115VAC is
present at CR #4 (BK) to neutral (W) but not at CR #6 (R) to neutral (W), replace
CR. If 115VAC is present at CR #6 (R) and Comp or ConFM are not energized,
check Comp start components, Comp protector (internal on 1-section, external
on 2-section), and Comp motor winding continuity. If ConFM is not energized,
check ConFM fan blades for binding and motor winding continuity.
EvapFM
: Confirm EvapFM icon turns on and EvapFM energizes. If not, confirm
doors are closed and DS engaged. Next, check for 115VAC at CM F5 (Y or
W/BU) to neutral (W). If 115VAC is not present, replace CM. If 115VAC is present,
check for 115VAC at DSR #4 (DBU) to neutral (W). If 115VAC is not present,
check for 115VAC at DSR #6 (Y or W/BU) to neutral (W). If 115VAC is present
on DSR #6 (Y or W/BU) to neutral (W) and not on DSR #4 (DBU) to neutral (W),
replace DSR. If 115VAC is present on DSR #4 (DBU) to neutral (W) and EvapFM
is not energized, check EvapFM blades for binding and EvapFM continuity.
(2)
15-min. temperature display delay timer terminates
: 12 min. after Comp,
ConFM, and EvapFM energize, "dEF" is replaced by cabinet temperature on
display. If not, replace CM.
Legend:
CM
–control module;
Comp
–compressor;
ConFM
–condenser fan motor;
CR
–compressor relay;
CTh
–cabinet thermistor;
DH
–defrost heater;
DrH
–drain heater;
DSR
–door switch relay;
DT
–defrost thermostat;
DTh
–defrost
thermistor;
EvapFM
–evaporator fan motors;
HPS
–high-pressure switch;
MH
–mullion heater;
PH
–perimeter heater;
TXV
–thermostatic expansion valve
