Bally Walk-In Cooler Error Code PrF: Process Failure
PrF, Process Failure, on a Bally walk-in evaporator with the SmartVap+ controller means the basic display is not communicating with the controller. The manual lists the trigger only. Check that the display is plugged in and call a technician.
Low: the display link is lost, but the controller may still be running the evaporator.
- Code
- PrF
- Maker
- Bally
- Equipment
- Walk-in coolers & freezers
- Applies to
- SmartVap+ evaporator controller (on-board display / dashboard display), used with Bally walk-in evaporators
What does Bally error code PrF mean?
On some SmartVap+ installations a basic display is a separate unit that connects to the controller and shows its readings and alarms. The controller and display keep exchanging information. If the display stops communicating, the controller raises the Process Failure alarm and shows PrF. The name sounds severe but the manual's Alarm Status Menu defines it narrowly: the basic display is not communicating with the controller. It gives no repair steps and no information about what the evaporator does while the link is down. A likely reading is that the controller continues to control the evaporator and that you have simply lost your view into it, so check the room temperature by other means. The link between controllers, which is CoA, is a separate alarm.
Affected models and control systems
The SmartVap+ evaporator controller with a basic display, used with Bally walk-in evaporators. The manual lists PrF in the Alarm Status Menu, and it applies where a basic display is fitted.
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
- PrF shows in the active alarm list
- The basic display is blank, frozen or shows no readings
- The controller may still be running the evaporator
Possible causes
Listed in Bally's documentation
- Basic Display is not communicating to the controller
Other likely causes — what usually sits behind error code PrF on this control. A technician confirms which one it is before any part is replaced.
- Display cable unplugged or loose at the display or controller
- Display cable damaged where it runs along the evaporator
- Display without power or restarting
- Moisture in the display connector
Safe checks before calling for service
- Check that the display is lit and its cable is firmly plugged in where you can reach it without opening panels.
- Check the room temperature with a separate thermometer to confirm the walk-in is cooling.
- Try Clear Alarms (CLA, press and hold) if the controller allows it, and see whether PrF returns.
- Note whether the display was ever working and what changed, and tell the technician.
How a technician diagnoses error code PrF
- Read the controller's own alarms and confirm which display is attached.
- Check the display's power and cable at both ends.
- Inspect the cable for damage and the connectors for moisture or corrosion.
- Test the display on a known good cable or a spare display.
- Replace the cable or display after the test, then clear the alarm and confirm readings return.
- The cable ends at the controller inside the evaporator housing next to energized wiring.
- Whether the problem lies in the display, the cable or the controller port is found only by swapping and testing parts.
How error code PrF differs from similar codes
PrF is between the basic display and the controller. CoA is between bonded controllers, and EFL is the email alert.
Technical reference
- Document
- SmartVap+ Intuitive Evaporator Control Technology, Operating Instructions (Bulletin B30-SVP-OM-2.05, Part # 1107523)
- Edition
- B30-SVP-OM-2.05, firmware 2.05+, dated 17/09/21
- Models / control
- SmartVap+ evaporator controller (on-board display / dashboard display), used with Bally walk-in evaporators
- Section
- Alarm Status Menu, page 6 of the PDF
- 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 Bally walk-in cooler & freezer error codes
Has the evaporator stopped?
Not necessarily. The manual says the display is not communicating. Check the room temperature to be sure.
Is PrF a process problem in the walk-in?
No. The name is misleading. It reports a lost display link.
Will it clear on its own?
If a loose cable was the cause, reseating it may clear it. Otherwise it returns.
Need help with Bally error code PrF?
A technician confirms the cause on site and gives you the price in writing before any work starts.