Polar King Walk-In Cooler Error Code email failure: Alert Not Sent
The email failure alarm means the controller sent an email alert and the email server did not confirm it after seven tries in a row. The manual gives no repair steps for it. Check the walk-in's network connection and the email settings first, then clear the alarm from the menu.
Low: the manual does not link this alarm to cooling; it reports a failed notification.
- Code
- Email failure
- Maker
- Polar King
- Equipment
- Walk-in coolers & freezers
- Applies to
- Polar King walk-in coolers/freezers with KE2 Evaporator Efficiency Evap OEM board (Basic Display / Combo Display)
What does Polar King Email failure mean?
The KE2 evaporator controller can send alert emails when other alarms occur. After it sends one, it waits for the email server to confirm that the message was accepted. When no confirmation comes back, it tries again. The manual states that after seven consecutive attempts without a confirmation, the controller raises its own alarm called email failure. On the Combo Display this appears in the Alarms menu under that name. A Basic Display shows only a red or yellow alarm light. The alarm is about the notification path, not about the refrigeration. Temperatures and compressor control are not mentioned in connection with it. What it does tell you is that nobody received the alert that was meant to reach them, so any other alarm that triggered the email may have gone unreported. The manual lists the alarm and its trigger only, and does not name causes.
Affected models and control systems
Polar King walk-in coolers and freezers fitted with the KE2 Evaporator Efficiency Evap OEM board, shown on either a Basic Display or a Combo Display. The alarm name is readable only on the Combo Display.
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
- Red or yellow alarm light on a Basic Display
- email failure listed in the Alarms menu on a Combo Display
- Expected alert emails about the walk-in never arrive
Possible causes
Likely causes — what usually sits behind Email failure on this control. A technician confirms which one it is before any part is replaced.
- An email alert was not confirmed by the email server after seven consecutive attempts
- Network cable or switch port feeding the controller is unplugged or down
- Email server address or login saved in the controller no longer matches the mail account
- The site's internet connection was down when the alert was sent
- A mail server that now rejects messages from this sender
Safe checks before calling for service
- Check whether other devices on the same network can reach the internet right now.
- Look at the network cable at the controller end and at the switch or router for a loose plug or a dark link light.
- Open the Alarms menu on a Combo Display to see whether other alarms are listed that were meant to be emailed.
- After the network is working again, use the CLEAR ALARMS menu item to clear the alarm, as the manual describes.
- Note the date the alerts stopped arriving, and any recent changes to the internet service or email account.
How a technician diagnoses Email failure
- Confirm the controller has a valid network address and can reach the mail server's network.
- Review the email settings stored in the controller against the current mail account details.
- Test the cable and port, and test the mail account from another device with the same login.
- Send a test alert and watch whether the server confirms it.
- Clear the alarm and confirm it does not return after the next alert.
- The email settings include account details and server addresses that should be changed only by someone who manages the site's network.
- Testing the controller's network port may require opening the control enclosure, which holds live wiring.
How Email failure differs from similar codes
This is a different alarm from the FTP communication and SNTP Communication alarms, which name a different server. All three are network-related, but each points to a separate server setting.
Technical reference
- Document
- KE2 Evaporator Efficiency Installation Instructions N.1.1 (posted on polarking.com Downloads as ke2-installation.pdf; authored by KE2 Therm Solutions)
- Edition
- N.1.1 July 2015
- Models / control
- Polar King walk-in coolers/freezers with KE2 Evaporator Efficiency Evap OEM board (Basic Display / Combo Display)
- Section
- Alarms Status Menu (view only), p. 14 (Alarm Status Menu listed p. 13)
- 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 Polar King walk-in cooler & freezer error codes
Is the walk-in still cooling with an email failure?
The alarm concerns notification, and the manual does not link it to cooling. Still, check the box temperature, since a missed alert may have hidden another alarm.
Will the email failure alarm go away by itself?
The manual says to use CLEAR ALARMS. If the network problem remains, the alarm can return after the next failed alert.
Why does it say seven attempts?
The manual states the controller tries seven consecutive times for a confirmation before it raises this alarm.
Need help with Polar King Email failure?
A technician confirms the cause on site and gives you the price in writing before any work starts.