UniMac Washer-Extractor Error Code E db: Drive Balance Switch

What does UniMac error code E db mean?

E db is the drive balance switch error on UniMac UC-series washer-extractors (F-speed models only) and UW pocket hardmount machines. A balance switch tells the control when the drum is out of balance during extraction. At the start of the drain step, that switch input on the variable frequency drive should still be open. The control looked and found it already closed. Since that reading cannot be right at that point, the batch halts.

The code points to the balance switch circuit and not to how the load was packed. A balance switch input at the drive that reads closed too early is the first possibility. A damaged wire or connector on the balance switch can do it. A balance switch stuck or out of adjustment, or a drive input circuit that reads the switch wrongly, completes the list.

Switching the machine off clears the code. Open the door only when the lock has let go and the drum is at rest. Restart the cycle once.

Affected models and control systems

E db is listed for the CHM495R family washer-extractors (UC-series, F-speed models only) and the PHM1263R family pocket hardmount washer-extractors (UWL, UWN and UWU 035 to 125).

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 db as the drain step begins
• The batch stops before the extract
• The drum may sit full of wet linens
• The code returns at the next drain

Possible causes

Listed in UniMac's documentation

• A balance switch input at the drive that reads closed too early
• A damaged wire or connector on the balance switch
• A balance switch stuck or out of adjustment
• A drive input circuit that reads the switch wrongly

Other likely causes — what usually sits behind error code E db on this control. A technician confirms which one it is before any part is replaced.

• Switch arm held closed by a bent bracket or lint build-up
• Short between two switch wires where the harness rubs the frame
• Moisture in the switch housing that closes the contacts
• Drive input that stays closed because of a failed internal part

Safe checks before calling for service

How a technician diagnoses error code E db

1. Read the code and confirm it appears at the start of drain.
2. Lock out the machine and inspect the balance switch, bracket and arm.
3. Check the switch wiring for shorts and chafing.
4. Test the switch contacts open and closed with a meter.
5. Check the drive input and replace the switch, wiring or drive as the tests show.

How error code E db differs from similar codes

E db belongs to the drive balance switch input, while E FS reports the frame balance switch open on the same machines.

Technical reference

Document

Washer-Extractor Programming CHM495R_SVG, Part No. F8208501ENR10, March 2017, Error Codes (pp. 36-37)

Maker documentation

UniMac owner support

Edition

Part No. F8208501ENR10, March 2017

Models / control

CHM495R family washer-extractor front-end control (20-100 lb) / PHM1263R family pocket hardmount washer-extractor (UWL/UWN/UWU 035-125) front-end control

Section

Error Codes table, pp. 36-37 (E Pr only on Design 1 models; Ed01-Ed11 on Design 2 and 3 models)

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.