Booking today · Miami, Los Angeles, Houston, New York and San Diego · three-hour arrival windows Independent commercial equipment repair · Every maker on this site Mon–Fri 7:00 AM - 8:00 PM · Sat 8:00 AM - 6:00 PM
(844) 393-0816 Schedule a Visit
Error code · Kolpak · Walk-in coolers & freezers

Kolpak Walk-In Cooler Error Code DISP EXTERNAL ALARM 3: Display AUX3 Active

DISP EXTERNAL ALARM 3 means Display AUX3 FUNCTION is set to EXT ALARM and the digital input is active. Something wired to the Display's third auxiliary input is signaling a condition. Press ENTER to silence the alarm for one hour and identify the device.

Medium · inspection needed

Medium: an outside device is signaling a condition the controller cannot describe.

Schedule a Visit(844) 393-0816
Code
DISP EXTERNAL ALARM 3
Maker
Kolpak
Equipment
Walk-in coolers & freezers
Applies to
ArcticFox OEM Controller with Deluxe Display (Kolpak walk-ins)

What does Kolpak DISP EXTERNAL ALARM 3 mean?

The third auxiliary input on the Deluxe Display can be set as an external alarm input. When AUX3 FUNCTION is EXT ALARM, the Display reads the contact as a digital input. Active means the contact is in the state that counts as an alarm. As soon as it is, the text alarm DISP EXTERNAL ALARM 3 appears in the Alarms menu. Nothing in the manual identifies the connected equipment, since that is chosen at installation. The alarm continues while the input stays active, so it ends only when the equipment returns to normal, the wiring is corrected or the function is changed to something else. ENTER silences the alarm for one hour, after which it sounds again if the input is still active. The DISP prefix shows the signal arrived at the Display and not at the Main board's AUX3.

Affected models and control systems

ArcticFox OEM Controller with Deluxe Display on Kolpak walk-ins. This alarm refers to Display AUX3 and is listed in the Alarms menu on page 17.

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

  • DISP EXTERNAL ALARM 3 text in the Alarms menu
  • Audible alarm from the display
  • Equipment on the third Display input showing a tripped state
  • Alarm returning after the one-hour silence

Possible causes

Likely causes — what usually sits behind DISP EXTERNAL ALARM 3 on this control. A technician confirms which one it is before any part is replaced.

  • Equipment on Display AUX3 reporting a real condition
  • Contact stuck so the Display input never clears
  • Display AUX3 FUNCTION set to EXT ALARM when the input was meant for a sensor
  • Corrosion or a loose connection at the Display AUX3 terminal

Safe checks before calling for service

✓ What an operator can do
  1. Press ENTER to silence the alarm for 1 hour. It returns if the input stays active.
  2. Look at wiring labels or installation notes to find what AUX3 is connected to.
  3. Check that equipment from the outside for a warning light or trip indicator.
  4. Give the technician the alarm text, the equipment name, and how long the alarm has been active.

How a technician diagnoses DISP EXTERNAL ALARM 3

  1. Read the Display AUX3 FUNCTION setting.
  2. Identify the connected equipment and its state.
  3. Meter the input at the Display terminals and compare with the equipment's contact.
  4. Lift the wire to see whether the alarm clears.
  5. Repair the equipment or wiring, or set the function to match what is installed.
! Leave this to a technician
  • Display terminals are live, and the housing has to be opened to reach them.
  • A tripped input may be protecting equipment, so it should be understood before it is silenced.
  • Changing a function setting is programming that must match the installation.

Technical reference

Document
ArcticFox Deluxe Display - Original Instructions, Installation, Operation and Maintenance Manual
Edition
Part No. 500002385-4, 5/23
Models / control
ArcticFox OEM Controller with Deluxe Display (Kolpak walk-ins)
Section
ArcticFox OEM Controller - Alarms Menu, p.17
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.

→Same maker

Related Kolpak walk-in cooler & freezer error codes

AIR TEMP SENSORKolpak Walk-In Cooler Alarm AIR TEMP SENSOR: Return Air ProbeCOIL TEMP SENSORKolpak Walk-In Cooler Alarm COIL TEMP SENSOR: Evaporator ProbeEXCESS DEFROSTKolpak Walk-In Cooler Alarm EXCESS DEFROST: 32 Defrosts in 48 HoursHIGH AIR TEMPKolpak Walk-In Cooler Alarm HIGH AIR TEMP: Room Too WarmHIGH SUPERHEATKolpak Walk-In Cooler Alarm HIGH SUPERHEAT: Above Upper LimitLOW AIR TEMPKolpak Walk-In Cooler Alarm LOW AIR TEMP: Room Too ColdLOW SUPERHEATKolpak Walk-In Cooler Alarm LOW SUPERHEAT: Below Lower LimitPRESSURE SENSORKolpak Walk-In Cooler Alarm PRESSURE SENSOR: Suction Pressure ReadingSUCTION TEMP SENSORKolpak Walk-In Cooler Alarm SUCTION TEMP SENSOR: Open or ShortedAUX1 SENSORKolpak Walk-In Cooler Error Code AUX1 SENSOR: Main AUX1 Shorted or OpenAUX2 SENSORKolpak Walk-In Cooler Error Code AUX2 SENSOR: Main AUX2 Shorted or OpenAUX3 SENSORKolpak Walk-In Cooler Error Code AUX3 SENSOR: Main AUX3 Shorted or Open
DISP EXTERNAL ALARM 3Questions about Kolpak DISP EXTERNAL ALARM 3
Does the number 3 mean the third alarm that occurred?

No. It identifies the Display's third auxiliary input.

Can I stop the alarm by changing a setting?

A technician can change the function, but only if nothing should be wired there. Otherwise the cause needs fixing.

Is it the same as EXTERNAL ALARM 3?

No. EXTERNAL ALARM 3 comes from the Main AUX3 input. This one comes from the Display.

Book a visit

Need help with Kolpak DISP EXTERNAL ALARM 3?

A technician confirms the cause on site and gives you the price in writing before any work starts.

(844) 393-0816
Open the booking form
☎ Call our office ▤ Schedule a Visit