Wascomat Washer Error Code 28: CPU/DLCU Low Levels
Code 28 means the mechanical level monitor in the DLCU disagrees with the nominal value from the CPU and the electronic level check. A technician should check the level controller, its cables and the level hoses.
High: the two level monitors disagree, so the washer stops until the level system is verified.
What does Wascomat error code 28 mean?
The Compass control checks the water level two ways. The CPU and its electronic level check set a nominal value, and the DLCU has a mechanical level monitor of its own. If the mechanical monitor disagrees with the nominal value, the control shows ERROR 028 / CPU/DLCU LOW LEVELS. The manual lists four causes: a damaged level controller, cross talk in the level controller electrical system, leakage in the level controller air hoses, and an incorrect nominal value. The steps are to check the level controller function, with switch-on at 40 mm and switch-off at 15 mm Wg, to check the cables, which should read 0 V below 15 mm Wg and 5 V above 40 mm Wg, and to blow clean all level hoses. Those numbers give the technician a definite pass or fail test.
Affected models and control systems
Wascomat washer-extractors W465H-W4300H, W475S-W4330S and W475N-W4330N with the Compass Control, CPU board and DLCU.
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
- ERROR 028 / CPU/DLCU LOW LEVELS appears
- The cycle stops during fill or at a level step
- The water level seems wrong on the gauge
- The code returns on the same program step
Possible causes
Listed in Wascomat's documentation
- Damaged level controller
- Cross talk in level controller electrical system
- Leakage in level controller air hoses
- Incorrect nominal value
Other likely causes — what usually sits behind error code 28 on this control. A technician confirms which one it is before any part is replaced.
- A level hose cracked or loose at a fitting so pressure leaks away
- Water or foam in the hose that distorts the pressure signal
Safe checks before calling for service
- Switch the machine off and on, then run the program again.
- Look at the water level through the door and note whether it seems normal.
- Do not pull on hoses or open panels.
- Write down the program step where the code appears, and call us.
How a technician diagnoses error code 28
- Read the code and confirm it is 028.
- Check the level controller switch points: on at 40 mm Wg and off at 15 mm Wg.
- Check the cables for 0 V below 15 mm Wg and 5 V above 40 mm Wg.
- Blow clean all level hoses and check for leaks.
- Check the nominal value in the service program.
- Replace the level controller or hose if it fails.
- Switch point and voltage checks need a pressure source and a meter.
- Level hoses run through the cabinet near mains-powered parts.
- The nominal value is a machine setting, not a guess.
How error code 28 differs from similar codes
Code 28 is the low-level disagreement between the DLCU monitor and the CPU, while code 53 is the high-level disagreement.
Technical reference
- Document
- Service manual, Washer extractors W465H-W4300H, W475S-W4330S, W475N-W4330N, Type W3..., Compass Control
- Maker documentation
- Wascomat owner support
- Edition
- 438 9228-61/EN, 2011.08.25
- Models / control
- W465H-W4300H, W475S-W4330S, W475N-W4330N (Compass Control)
- Section
- Troubleshooting, Description of error codes and causes (manual pp. 108-138)
- 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 Wascomat washer error codes
What do 40 mm and 15 mm Wg mean?
They are the pressure switch points of the level controller, on at 40 mm and off at 15 mm of water gauge.
Is it a hose problem?
It can be. A leak in the air hoses can distort the level reading.
Is it the same as code 53?
No. Code 53 concerns the monitor not switching off at program start or end.
Need help with Wascomat error code 28?
A technician confirms the cause on site and gives you the price in writing before any work starts.