UniMac Washer-Extractor Error Code E d 24: Sustained Over Current
E d 24 is a fatal I2T hardware over current error on a UniMac QN washer-extractor. The drive measured too much current for too long and shut down. Switch off to reset, try a lighter load, and call us if it returns.
High: a fatal drive shutdown that returns until the rotor, windings or drive are checked.
- Code
- E d 24
- Maker
- UniMac
- Equipment
- Industrial laundry
- Applies to
- CHM1792C family washer-extractor (QN models, 20-100 lb) front-end control
What does UniMac error code E d 24 mean?
E d 24 is a fatal I2T hardware over current error on a UniMac QN washer-extractor such as the UCA020QN. Where E d 23 reacts to one sudden spike, this code reacts to time. The drive adds up how much current the motor draws and for how long. When the total passes a safe threshold, the drive treats that as a safety problem and shuts down. The cycle ends, and the code remains until power is cycled.
A motor draws a lot of current when it struggles. A locked rotor, a motor with failing windings, or a heavy drag on the drum each make it struggle for long stretches. The size and balance of the load matter too, since a very heavy or lopsided batch keeps the current high through the whole spin. The drive output stage is the last item on the list.
The maker's reset step is simply to switch the main power off. Because the cause can be mechanical or electrical, the manual asks for the rotor and phase windings to be checked.
Affected models and control systems
E d 24 is listed for the CHM1792C family, QN washer-extractors from 20 to 100 lb, with the front-end control and drive board. The manual's example is the UCA020QN.
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
- The display shows E d 24 partway through a spin
- The motor sounds strained or hums before the stop
- The drum is hard to turn by hand after shutdown
- The code appears more often on heavy loads
Possible causes
Listed in UniMac's documentation
- Rotor and drum freedom
- Motor phase windings
- Drive output
- Load size and balance
Other likely causes — what usually sits behind error code E d 24 on this control. A technician confirms which one it is before any part is replaced.
- Worn drum bearings that keep adding drag through the cycle
- Motor winding that is breaking down and draws more with every spin
- Loads that run over the rated capacity so the motor works at its limit
- Drive output stage that delivers more current than the motor needs
Safe checks before calling for service
- Switch the main power off to reset the error.
- Turn the empty drum by hand without forcing it, but only after power is off and the drum is still.
- Send through a lighter load and watch for the code.
- If E d 24 returns, note the load size and call us, since the maker asks for the rotor and phase windings to be checked.
How a technician diagnoses error code E d 24
- Read the code and ask what size of load ran before it.
- Lock out the machine and check that the drum and rotor turn freely.
- Measure the resistance of each motor phase winding and compare them.
- Check motor leads and the harness for damage that adds resistance.
- Check the drive output with the motor disconnected.
- Replace bearings, motor or drive depending on which check fails.
- Measuring motor phase windings means opening the cabinet on a 208 to 240 V machine.
- A drum that drags may need bearing work that is heavy and calls for the right tools.
- Separating a motor problem from a drive output problem needs a methodical set of electrical tests.
Technical reference
- Document
- Washer-Extractor Programming CHM1792C_SVG, Part No. F8641001ENR4, Error Codes Table 29 (pp. 100-107)
- Maker documentation
- UniMac owner support
- Edition
- Part No. F8641001ENR4, January 2020
- Models / control
- CHM1792C family washer-extractor (QN models, 20-100 lb) front-end control
- Section
- Error Codes, Table 29, pp. 100-108 (PDF pages equal printed pages)
- 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 UniMac industrial laundry error codes
Could my loads be too big?
They might be. Try a lighter batch, but if the code appears on a small load too, the problem lies in the motor or drive.
Will switching off fix it?
It clears the code. The underlying drag or winding problem will bring it back.
How does this differ from E d 31?
Both involve too much current. E d 24 is the fatal time-based trip, while E d 31 is the overload current detection error.
Need help with UniMac error code E d 24?
A technician confirms the cause on site and gives you the price in writing before any work starts.