What does Sullair VSD Drive Fault 14 (over-temperature) mean?
Short answer: VSD heatsink over-temperature. If your Sullair Supervisor Controller (VSD drive faults) is showing Drive Fault 14 (Over-temperature), the controller has logged a specific, documented condition. This page covers what it means, what causes it, what you can safely fix yourself, and when — and why — it takes a technician.
What exactly is the machine telling you?
The variable speed drive heatsink exceeded 194°F (90°C); a warning is issued at 185°F (85°C). Usually caused by restricted cooling airflow, dust buildup on the heatsink, or high ambient temperature.
Which machines show this?
variable-speed Sullair rotary screw packages from the Supervisor era, where the Supervisor controller passes through numbered fault codes from the variable frequency drive itself — Drive Fault 14 (heatsink over-temperature, tripping at 194 °F with a warning at 185 °F), Drive Fault 9 (DC-link undervoltage), and E-stop codes like VSD Code 51. These are the drive's own protections talking, layered on top of the compressor's T/P channel faults. Practical tip: split the diagnosis in two — heat-related drive faults usually trace to cabinet airflow and dust, while voltage-related ones trace to the plant supply; log the time of each event so an electrician can match it against facility power records.
What causes it?
- Restricted cooling airflow around the drive cabinet
- Dust buildup on the drive heatsink
- High ambient temperature (heatsink faults at 194°F, warns at 185°F)
Can you fix it yourself?
Partly — airflow and room-temperature fixes are in-house; heatsink cleaning is not, because it lives inside the drive cabinet.
Step by step — what to try, in order:
- Check for unrestricted cooling airflow around the drive cabinet
- Reduce ambient temperature or improve room ventilation
- Schedule professional cleaning of the heatsink if dust buildup is suspected
When do you need a technician — and why?
The drive cabinet holds capacitors that stay charged after power-off, so heatsink cleaning and settings verification are service-only work.
If it does come to a service call and you're in Nashville, TN or Birmingham, AL, we maintain independently compiled lists of local companies that service industrial air compressors — real businesses with verified contact information, none of whom paid to be listed.
Related questions
What does Drive Fault 14 (Over-temperature) mean on a Sullair Supervisor Controller (VSD drive faults)?
VSD heatsink over-temperature. The variable speed drive heatsink exceeded 194°F (90°C); a warning is issued at 185°F (85°C). Usually caused by restricted cooling airflow, dust buildup on the heatsink, or high ambient temperature.
Can I fix Drive Fault 14 (Over-temperature) on a Sullair Supervisor Controller (VSD drive faults) myself?
Partly — airflow and room-temperature fixes are in-house; heatsink cleaning is not, because it lives inside the drive cabinet.
When does Drive Fault 14 (Over-temperature) on a Sullair Supervisor Controller (VSD drive faults) need a technician?
The drive cabinet holds capacitors that stay charged after power-off, so heatsink cleaning and settings verification are service-only work. Call service to clean the heatsink and verify drive settings — the drive cabinet contains high-voltage components.
Verified against service documentation: Sullair Supervisor Controller (VSD drive faults) documentation for Drive Fault 14 (Over-temperature) (best-aire.com)