15
e)
Comp and ConFM Diagnosis
: Confirm Comp and ConFM energize. If not, 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 at CM C1 (R or V) to neutral (W), check for 115VAC at
CR #0 (GY or P) to CR #1 (W). If 115VAC is not present, check continuity of HPS.
If open, allow time for HPS to reset. If HPS does not reset, see "e) HPS Activation"
below. If HPS is closed and 115VAC is present, check for 115VAC at CR #4 (BK)
and CR #6 (R) to neutral (W). If 115VAC is present at CR #4 (BK) and not at CR
#6 (R), replace CR. If 115VAC is present at CR #6 (R) to neutral (W) and ConFM
is energized but Comp is not: On 1-section; Give time for internal protector to cool
and reset. Next, check run capacitor, start capacitor, start relay, and Comp motor
windings. If Comp does not start, replace Comp. On 2-section; Check for 115VAC
at Comp external protector to neutral (W). If 115VAC is not present, give time for
Comp external protector to cool and reset. If Comp external protector does not reset,
replace Comp external protector. If 115VAC is present, check run capacitor, start
capacitor, start relay, and Comp motor windings. If ConFM is not energized, check
ConFM fan blades for binding and motor winding continuity.
If Comp and ConFM are energized and the cabinet does not cool down, check for a
restriction in the refrigeration circuit, correct TXV operation, and correct refrigerant
charge.
f)
HPS Activation
: Confirm ConFM is energized and fan blade turns freely. Confirm
condenser coil is not clogged or restricted. Confirm there are no restrictions in the
refrigeration circuit (TXV and drier). Let refrigeration circuit pressures equalize.
If HPS does not reset and pressures are equalized, replace HPS. If pressures are
not equalized, reclaim refrigerant and diagnose refrigeration circuit restriction.
8)
Cool Down Achieved–
CTh cools to 3°F (1.7°C) below setpoint. EvapFM, MH, and
PH continue. Comp and ConFM de-energize.
Diagnosis
: Confirm Comp and ConFM
de-energize. If not, and Comp and ConFM were energized longer than 2 min., check
CTh status. See "II.D. Thermistor Check." If CTh ohm reading is in proper range and
Comp and ConFM continue longer than 2 min., check for 115VAC at CM C1 (R or V) to
neutral (W). If 115VAC is present, replace CM. If 115VAC is not present and Comp and
ConFM continue, check CR #6 (R) to neutral (W). If 115VAC is present, replace CR.
9)
Defrost–
The defrost icon turns on and "dEF" is displayed during defrost. There is a
5-min. minimum defrost time and a 1-hr. maximum defrost time.
1a)
Temperature/Time-Initiated
: DTh cools to 32°F (0°C), 4-hr. cumulative Comp
run timer starts. Once DTh is at or below 32°F (0°C) with 4-hr. cumulative Comp
run timer satisfied (Comp energized more than 4 hrs.), defrost icon turns on and
"dEF" is displayed. MH and PH continue. DH and DrH energize. If on, Comp and
EvapFM icons turn off. Comp, ConFM, and EvapFM de-energize.
1b)
Manually-Initiated
: To initiate a manual defrost, press the manual defrost button
on display. Comp and EvapFM icons turn off. Defrost icon turns on and "dEF" is
displayed. MH and PH continue. DH and DrH energize, Comp and EvapFM icons
turn off, Comp, ConFM, and EvapFM de-energize.
