What does Gardner Denver shutdown 165 DC power low mean?
Short answer: Low 24 VDC control power. If your Gardner Denver AirSmart controller is showing SHUTDOWN #165 DC POWER LOW, 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 24 VDC supply feeding the controller dropped below roughly 18.5 VDC, so the controller shut down. The documented action is to check the 24 VDC power supply.
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?
- Facility voltage dipped or browned out, dragging the 24 VDC control supply below ~18.5 VDC
- The control power supply itself weakening (the repeat-trip case)
Can you fix it yourself?
Yes, if it followed a known power dip — reset once power is stable. If it keeps happening on clean power, the control power supply needs testing, which isn't operator work.
Step by step — what to try, in order:
- Check whether facility voltage dipped or browned out at the time of the fault
- Press Stop/Reset and attempt a restart once power is stable
When do you need a technician — and why?
Testing the 24 VDC power supply happens inside the live electrical cabinet under lockout rules, with the fault sometimes only visible under load on a meter.
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 #165 DC POWER LOW mean on a Gardner Denver AirSmart controller?
Low 24 VDC control power. The 24 VDC supply feeding the controller dropped below roughly 18.5 VDC, so the controller shut down. The documented action is to check the 24 VDC power supply.
Can I fix SHUTDOWN #165 DC POWER LOW on a Gardner Denver AirSmart controller myself?
Yes, if it followed a known power dip — reset once power is stable. If it keeps happening on clean power, the control power supply needs testing, which isn't operator work.
When does SHUTDOWN #165 DC POWER LOW on a Gardner Denver AirSmart controller need a technician?
Testing the 24 VDC power supply happens inside the live electrical cabinet under lockout rules, with the fault sometimes only visible under load on a meter. Call a technician if the fault repeats — testing the control power supply is electrical-cabinet work.
Verified against service documentation: Gardner Denver AirSmart controller documentation for SHUTDOWN #165 DC POWER LOW (best-aire.com)