16
The green LED’s 1-4 represent the corresponding relays and energize and sequence 5
seconds from initial start-up as follows:
Sequence Step
LED’s on Length:
Min.
Max.
Avg.
1 Minute Fill Cycle
LED4
60 sec.
Harvest Cycle
LED1, 4, & 2
2 min.
20 min.
3-5 min.
Freeze Cycle
LED1
5 min.
60 min.
30-35 min.
Reverse Pump Out
LED1, 3, & 2
10 sec.
20 sec.
Factory set.
{LED 1 – Comp; LED 2 - HGV/CFM; LED 3 – PM; LED 4 - WV}
The built in safeties shut down the unit and have alarms as follows:
1 beep
every 3 sec. =
High Evaporator Temperature
>127 ° F.
Check
for defrost problem (stuck HGV or relay), hot water entering unit, stuck
headmaster, or shorted thermistor.
2 beeps
every 3 sec. =
Defrost Back Up Timer
. Defrost >20 minutes.
Orange LED marked 20 MIN energizes.
Check
for open thermistor, HGV not opening, TXV leaking by, low charge, or inefficient
compressor.
3 beeps
every 3 sec. =
Freeze Back Up Timer
. Freeze > 60 minutes.
Yellow LED marked 60 MIN energizes.
Check
for F/S stuck closed (up), WV leaking by, HGV leaking by, TXV not feeding
properly, low charge, or inefficient compressor.
To manually reset the above safeties, depress white alarm reset button with the power
supply ON.
6 beeps
every 3 sec. =
Low Voltage
. Voltage is 92 Vac or less.
7 beeps
every 3 sec. =
High Voltage
. Control voltage > 147 Vac ±5%.
The red LED will de-energize if voltage protection operates.
The voltage safety automatically resets when voltage is corrected.
The
Output Test
switch “S3” provides a relay sequence test. With power OFF, place S3
ON and switch power to ICE. The correct lighting sequence should be none, 2, 3, 4, 1, & 4,
normal sequence every 5 seconds. S3 should remain in the “OFF” position for normal
operation.
Machines
with
mechanical
bin control
ONLY
4 beeps
every 3 sec. =
Short Circuit
between the K4 connection on
the control board and the bin control relay. Check connections and
replace wire harness if necessary.
5 beeps
every 3 sec. =
Open Circuit
between the K4 connection
on the control board and the bin control relay. Check connections and
replace wire harness if necessary.
Summary of Contents for KM-500MAH
Page 28: ...28 III TECHNICAL INFORMATION 1 WATER CIRCUIT AND REFRIGERANT CIRCUIT a KM 500MAH ...
Page 29: ...29 b KM 500MWH ...
Page 30: ...30 c KM 500MRH ...
Page 34: ...34 b KM 500MRH with auxiliary codes M 2 and after ...
Page 35: ...35 3 TIMING CHART ...
Page 36: ...36 ...
