Service Manual

17
5a) Initial Harvest Cycle – LEDs 1, 4, and 2 are on. WV and X11 relay continue. Comp,
FMR, HGV, X10, and X12 relays energize. CBmonitors the warming of the evaporator
via the thermistor located on the suction line. When the thermistor reaches 48°F (9°C),
CB reads 3.9 kΩ from the thermistor and turns harvest termination over to the harvest
timer (S4 dip switch 1 & 2 and S5dip switch 4). WV and X11 relay are energized during
harvest for a maximum of 6 min. or the length of harvest minus HPT setting (S4 dip
switch 6), whichever is shorter. See step 5b below.
a) Comp Diagnosis: Check that evaporator is warming. Ifnot, conrm that Comp
energizes. If not, check for 115VAC at CB K1 #1 (V) or #9 (V) to neutral (W).
If115VAC is not present, check for 115VAC at CB K1 #7 (BR) or #10 (BR) to neutral
(W). If115VAC is present at #7 (BR) or #10 (BR) and not at #1 (V) or #9(V),
replaceCB. If 115VAC is present, check for 115VAC MC solenoid. If 115VAC is
present, conrm contacts are closed. If not, replace MC. If MC contacts are closed,
check Comp start and run capacitors, start relay (single phase), and Comp motor
winding.
b) HGV Diagnosis: If Comp is energized and evaporator is not warming, check that
HGV energizes and opens. Check for 115VAC at CB K1 #2 (P) to neutral (W).
If115VAC is not present and LED 2 is on, replace CB. If 115VAC is present, check for
115VAC at HGV coil and check HGV coil continuity. Replace as needed.
c) LLV Diagnosis: Conrm that LLV is de-energized and closed (not bypassing).
Ifenergized, replace CB. If de-energized and bypassing, replace LLV.
5b) Harvest Pump Time (Harvest Assist) – LEDs 1, 3, and 2 are on. When the thermistor
reaches 48°F (9°C), CB reads 3.9 kΩ from the thermistor and turns harvest termination
over to the harvest timer (S4 dip switch 1 & 2 and S5 dip switch4). WhenWV
de-energizes, LED 4 turns off, X11 relay de-energizes and LED 3turns on. PM
energizes. Comp, FMR, HGV, X10 and X12 relays continue.
Diagnosis: Place a thermometer on the suction line next to the thermistor. Has it
warmed to 48°F (9°C) or warmer? Conrm thermistor status. See "II.G. Thermistor
Check." If the thermistor reading is in proper range, dip switch 7 is on, and PM does
not energize before harvest terminates, replace CB. If WV continues, check for 115VAC
at CB K1 #6 (O). If115VAC is present, and LED 4 is off, replace CB. If LED 3is on and
PM is not energized, check for 115VAC at CB K1 #5(DBU). If115VAC is not present,
replace CB. If 115VAC is present and PM is not energized, check for 115VAC at X10relay
terminal #7 (Y) to neutral (W). If 115VAC is not present, check for 115VAC at X10 relay
terminal #3 (P) to neutral (W) and X10 relay terminal #5 (Y) to neutral (W). If 115VAC is
present on terminal #3(P) and not on terminal #5 (Y), replace X10 relay. If 115VAC is
present on X10 relay terminal #7 (Y) and PM is not energized, check for 115VAC at X10
relay terminal #4 (R) to neutral (W) and terminal #6 (DBU) to neutral (W). If 115VAC is
present on terminal #6(DBU) and not on terminal #4 (R), replace X10relay. If 115VAC
is present on X10relay terminal #4 (R), check control switch contact continuity between
terminals #4(R) and #5(W/R). Ifcontacts are open, replace control switch. If contacts
are closed and 115VAC is present between control switch terminal #5(W/R) and
neutral(W), check PM capacitor and motor winding continuity.