Hoshizaki Comprehensive Guide to LED Lights and Alarm Safeties in Refrigerators

f) LED Lights and Audible Alarm Safeties

The red LED indicates proper control voltage and will remain on unless a control voltage problem occurs. At startup a 5 second delay occurs while the board conducts an internal timer check. A short beep occurs when the power switch is turned OFF.

The green LEDs 1 through 4 energize and sequence from initial startup as listed in the table below. Note that the order of the LEDs from the outer edge of the board is 1, 4, 3, 2. For more information, see "II.B. Sequence of Operation."

Sequence Step	LED	Energized		Time LEDs are On
		Components	Min.	Max.	Avg.
1 Minute Fill Cycle	4	WV			60 seconds
Harvest Cycle	1, 4, and 2	WV, HGV,	2 minutes	20 minutes	3 to 5 minutes
		Comp, FMR
Freeze Cycle	1	Comp, PM,	5 minutes	freeze timer	30 to 35 minutes
		FMR/FMS,		setting
		LLV
Reverse Pump Out	1, 3, and 2	Comp, HGV,	10 seconds	20 seconds	factory setting
		PM, FMR

The built in safeties shut down the unit and have alarms as follows:

No. of Beeps	Type of Alarm	Notes
(every 3 sec.)
1	High Evaporator Temp.	Check for harvest problem (stuck HGV or
	(temperature > 127°F)	relay), hot water entering unit, stuck HM,
	(53°C)	or shorted thermistor.
2	Harvest Backup Timer	Orange LED marked H TIMER lights up.
	(harvest > 20 min. for two	Check for open thermistor, HGV not
	cycles in a row)	opening, TXV leaking by, low charge, or
		inefficient compressor.
3	Freeze Timer	Yellow LED marked F TIMER lights up.
	(freeze > specified setting	Check for F/S stuck closed (up), WV
	for two cycles in a row)	leaking by, HGV leaking by, TXV not
	Timer is factory set using	feeding properly, low charge, HM not
	dip switches 9 & 10	bypassing, or inefficient compressor.

To manually reset the above safeties, press the alarm reset button with the power supply on.

6	Low Voltage	Red LED will turn off if voltage protection
	(92Vac ±5% or less)	operates.
		The control voltage safeties automatically
7	High Voltage
		reset when voltage is corrected.
	(147Vac ±5% or more)

Legend: Comp–compressor; FMR–remote fan motor; FMS–self-contained fan motor; F/S–float switch; HGV–hot gas valve; HM–headmaster (C.P.R.); LLV–Liquid Line Valve; PM–pump motor; TXV–thermostatic expansion valve; WV–inlet water valve

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