Kolpak Walk-In Cooler Error Code HIGH MONITOR TEMP3: Monitor3 Above Limit
HIGH MONITOR TEMP3 means the Display Monitor3 temperature is above MON TMP3 HI ALRM for longer than MON TMP3 AL DLY. The third monitored spot is warmer than its limit. Press ENTER to silence the alarm for one hour and check what that sensor is watching.
Medium: a monitored area is above its high limit, and product there may be at risk.
- Code
- HIGH MONITOR TEMP3
- Maker
- Kolpak
- Equipment
- Walk-in coolers & freezers
- Applies to
- ArcticFox OEM Controller with Deluxe Display (Kolpak walk-ins)
What does Kolpak HIGH MONITOR TEMP3 mean?
Monitor3 is the third extra temperature input the Deluxe Display can read. Like the others, it has a high limit, here MON TMP3 HI ALRM, and a delay, MON TMP3 AL DLY. The controller does nothing while the reading is under the limit. Once it goes over, a timer starts, and if the reading stays over the limit for longer than the delay, the text alarm HIGH MONITOR TEMP3 appears in the Alarms menu. The delay protects against short, harmless warm periods, like a door opened to load a pallet. The manual does not state what sensor is wired as Monitor3, so that information comes from the installer. Because the reading is valid, this is a temperature alarm rather than a wiring alarm. It sounds again after one hour if the reading stays above the limit.
Affected models and control systems
ArcticFox OEM Controller with Deluxe Display on Kolpak walk-ins. The manual lists HIGH MONITOR TEMP3 in the Alarms menu on page 17. It needs a Monitor3 sensor.
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
- HIGH MONITOR TEMP3 text in the Alarms menu
- Audible alarm from the display
- Monitor3 temperature reading above its normal level
- Area around the sensor feeling warm
Possible causes
Likely causes — what usually sits behind HIGH MONITOR TEMP3 on this control. A technician confirms which one it is before any part is replaced.
- Watched area warming because of door traffic, load or reduced cooling
- Monitor3 sensor mounted near warm air or a heat source
- High limit MON TMP3 HI ALRM set low for what the sensor watches
- Delay MON TMP3 AL DLY too short for normal activity
Safe checks before calling for service
- Press ENTER to silence the alarm for 1 hour. It returns if the reading stays high.
- Identify where Monitor3 is, and take a thermometer reading at that spot.
- Close the door, and clear anything blocking airflow from the evaporator.
- Note the displayed Monitor3 temperature against the thermometer for the technician.
How a technician diagnoses HIGH MONITOR TEMP3
- Read MON TMP3 HI ALRM and MON TMP3 AL DLY.
- Compare the Monitor3 reading with a calibrated thermometer.
- Check cooling performance, defrost state and door seal.
- Review sensor placement.
- Fix the cause or reposition the sensor, and confirm the reading drops below the limit.
- Cooling performance checks involve refrigerant gauges.
- Limit and delay values are programming that belongs with the installation.
- Sensor testing connects a meter to live controller inputs.
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.
Related Kolpak walk-in cooler & freezer error codes
What is Monitor3?
It is the third extra temperature input on the Display. The installation decides what it watches.
Is this different from HIGH MONITOR TEMP3 ALARM?
The condition is alike, but that name belongs to the stand-alone Display. This one belongs to the OEM controller with Display.
Should I move product?
Check the real temperature with a thermometer. If it is above your safe limit, move product and follow your own food safety rules.
Need help with Kolpak HIGH MONITOR TEMP3?
A technician confirms the cause on site and gives you the price in writing before any work starts.