Hoshizaki Ice Machine 7 Beeps: High Voltage
Seven beeps on a Hoshizaki KM or KMH ice machine mean the control voltage is at 147 VAC plus or minus 5% or more. The machine stops and resets automatically once the voltage is corrected. Correct the supply; no reset is needed.
High: the machine will not run while the control voltage is too high.
- Code
- 7 beeps (High Voltage)
- Maker
- Hoshizaki
- Equipment
- Ice machines
- Applies to
- KM / KMD / KML / KMS crescent cubers, "E", "G" and "J" control boards (KM-1301 to KM-2600, KMD-460/530, KML-250 to 631, KMS-822); DCM cubelet ice maker/dispenser and F-2001 / F-1501 "J" flakers (5-second beep interval)
What does Hoshizaki error code 7 beeps mean?
The control board monitors the control voltage on both sides of the normal range. When it rises to 147 VAC plus or minus 5% or more, the board stops the machine to protect its parts and sounds seven beeps. On KM E and G boards the red POWER OK LED goes off, and on DCM and F flakers the green POWER LED goes off. Nothing needs to be pressed. The safety resets by itself when the voltage comes back into range, and the manual's action is only to correct the supply voltage. A voltage that high usually comes from outside the machine: a supply tap that is set too high, a utility swing, or a transformer that was wired to the wrong tap. Because high voltage can shorten the life of the board, relays and motors, the machine stops instead of continuing. A meter reading at the machine is the first step, and it is best taken while the machine is idle and again when it starts.
Affected models and control systems
KM-1301SAH/3 through KM-2500 and KMH-2000 stackable cubers with E and G control boards; the same table appears in the manual for the KMD-460/530 and KML-250 to 631 G-board models. The same alarm is used on DCM and F flakers, per the flaker instruction manual.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- Seven beeps
- Power light off (red POWER OK on KM E and G boards, green POWER on DCM and F flakers)
- Machine stopped and not making ice
- Other equipment on the same supply behaving oddly
Possible causes
Likely causes — what usually sits behind error code 7 beeps on this control. A technician confirms which one it is before any part is replaced.
- Control voltage at 147 VAC plus or minus 5% or more
- A building supply running above its normal level at off-peak times
- A control transformer connected to a higher tap than the supply needs
- A neighboring heavy load switching off and letting the supply voltage rise
Safe checks before calling for service
- Check whether the beeps come at a particular time of day.
- Do not press anything; the machine resets itself when the voltage is corrected.
- Ask the building electrician whether the supply voltage has changed.
- Tell the technician when it happens and the date, and leave the machine off if it keeps tripping.
How a technician diagnoses error code 7 beeps
- Measure the supply voltage at the machine, idle and running.
- Compare the reading with the machine's nameplate range.
- Check the control transformer taps and wiring.
- Check for a supply problem upstream with the building electrician.
- Confirm the POWER light returns once the supply is corrected.
- Voltage and transformer tap checks are live electrical work.
- An over-voltage supply is a building electrical issue that can damage other equipment.
- Choosing the right transformer tap needs the wiring diagram for the exact model.
How error code 7 beeps differs from similar codes
7 beeps is high control voltage; 6 beeps is the low-voltage counterpart. The power light is red POWER OK on KM E and G boards and green POWER on DCM and F flakers.
Technical reference
- Maker documentation
- Hoshizaki owner support
- Edition
- Number 73208, issued 7-7-2015, revised 8-11-2015
- Models / control
- KM / KMD / KML / KMS crescent cubers, "E", "G" and "J" control boards (KM-1301 to KM-2600, KMD-460/530, KML-250 to 631, KMS-822); DCM cubelet ice maker/dispenser and F-2001 / F-1501 "J" flakers (5-second beep interval)
- Section
- III.B. LED Lights and Audible Alarm Safeties, pp. 49-50; flaker manual L. Alarm Safeties p. 40
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related Hoshizaki ice machine error codes
Is high voltage dangerous for the machine?
It can be, which is why the control stops the machine. The manual says to correct the supply voltage.
Do I need to reset it?
No. The safety resets automatically once the voltage is corrected.
Why is the light a different color on my flaker?
The manual describes a green POWER LED on DCM and F flakers and a red POWER OK LED on KM E and G boards.
Need help with Hoshizaki error code 7 beeps?
A technician confirms the cause on site and gives you the price in writing before any work starts.