What does Gardner Denver shutdown 150 motor overtemp mean?
Short answer: Main motor over-temperature. If your Gardner Denver AirSmart controller is showing SHUTDOWN #150 MOTOR OVERTEMP, 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 digital input programmed for motor over-temperature tripped, meaning the main motor (or its overload relay) got too hot.
Which machines show this?
Gardner Denver rotary screw compressors fitted with the first-generation AirSmart microprocessor controller — a wide range of oil-injected packages, including VFD-equipped variable-speed units where the controller supervises the drive. The first-generation AirSmart reports problems as numbered codes: SHUTDOWN #1xx and #2xx faults that stop the machine, and ADVISORY #3xx warnings that let it keep running while flagging maintenance. That numbering matters when you search — the later AirSmart G2 dropped the numbers and displays plain-text fault names instead, so a numbered code on the screen tells you that you are on the earlier controller. Shutdowns clear with Stop/Reset once the machine has stopped; advisories acknowledge with the Enter key.
What causes it?
- Main motor overheated after running hard in a hot, poorly ventilated room
- Motor cooling vents blocked with dust
- Overload relay tripping — either doing its job or set wrong (the repeat case)
Can you fix it yourself?
Sometimes — let the motor cool fully, clean its vents with power off at the machine controls, improve ventilation, and restart under reduced load. A second trip is not a reset-and-hope situation.
Step by step — what to try, in order:
- Let the motor cool completely before any restart attempt
- Check for blocked motor cooling vents and clean exterior dust with power off at the machine controls
- Improve room ventilation if ambient temperature is high
- Press Stop/Reset and restart under reduced load if possible
When do you need a technician — and why?
Overload relay settings and motor winding condition are checked with electrical test gear inside the high-voltage cabinet — misjudging either can burn out the most expensive electrical component on the package.
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 SHUTDOWN #150 MOTOR OVERTEMP mean on a Gardner Denver AirSmart controller?
Main motor over-temperature. The digital input programmed for motor over-temperature tripped, meaning the main motor (or its overload relay) got too hot.
Can I fix SHUTDOWN #150 MOTOR OVERTEMP on a Gardner Denver AirSmart controller myself?
Sometimes — let the motor cool fully, clean its vents with power off at the machine controls, improve ventilation, and restart under reduced load. A second trip is not a reset-and-hope situation.
When does SHUTDOWN #150 MOTOR OVERTEMP on a Gardner Denver AirSmart controller need a technician?
Overload relay settings and motor winding condition are checked with electrical test gear inside the high-voltage cabinet — misjudging either can burn out the most expensive electrical component on the package. Call a technician if it trips again — overload relay settings and motor condition require electrical diagnosis.
Verified against service documentation: Gardner Denver AirSmart controller documentation for SHUTDOWN #150 MOTOR OVERTEMP (best-aire.com)