MEIKO Commercial Dishwasher Error Code ERR 204: No Level Change After Rinse
ERR 204 on the UPster U 400 M2 display reads No change yet detected at the boiler level switch after the rinse time expired (with pressure booster pump). The manual gives the same causes as ERR 203 and says to call a service technician.
High: the boiler level check fails after rinsing and the machine stops until it is repaired.
- Code
- ERR 204
- Maker
- MEIKO
- Equipment
- Dish machines
- Applies to
- Meiko UPster U 400 M2 glass and dishwasher, M001DWUC10M2-10
What does MEIKO error code ERR 204 mean?
During rinsing, the boiler should empty as water is pushed through the rinse arms, and the boiler level switch should change state as the level falls. If the rinse time runs out and the switch has not yet changed, the control shows ERR 204, No change yet detected at the boiler level switch after the rinse time expired (with pressure booster pump). The manual says the causes are the same as ERR 203: a defective pressure booster pump, a disconnected plug connection, a defective start capacitor, a defective boiler level switch, or no signal to or from the pump and the I/O board. It states that it is not possible to continue working and that a technician should be called. The practical difference from ERR 203 is the timing of the check, since it comes after the rinse time ends. The display reads No change yet detected at the boiler level switch after the rinse time expired.
Affected models and control systems
This code is listed for the Meiko UPster U 400 M2 glass and dishwasher, type M001DWUC10M2-10, in section 9.6.1 Messages (the ERR table on printed pp. 34-35).
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
- ERR 204 with the text No change yet detected at the boiler level switch after the rinse time expired
- Rinse seeming weak or ending without proper flow
- Machine stopped after the rinse stage
Possible causes
Likely causes — what usually sits behind error code ERR 204 on this control. A technician confirms which one it is before any part is replaced.
- Pressure booster pump defective
- Plug connection disconnected
- Start capacitor defective
- Boiler level switch defective
- No signal to or from the pump and the I/O board
- Rinse arm nozzles clogged with scale, so water leaves the boiler too slowly
- Pump running weakly because of a worn motor or low capacitor value
Safe checks before calling for service
- Check the rinse arms and nozzles for visible scale or blockage, using the machine's normal cleaning access.
- Switch the machine off and on once and run a short cycle to see whether ERR 204 returns.
- Listen for the booster pump during the rinse and note whether it runs normally.
- Write down when ERR 204 shows and how the rinse looked, for the service call.
How a technician diagnoses error code ERR 204
- Read the message history and see whether ERR 203 and ERR 204 appear together.
- Check the pump plug and wiring.
- Test the start capacitor and pump motor.
- Check the boiler level switch response during a rinse.
- Inspect the rinse arms and nozzles for restriction.
- Replace the failed part and run a full rinse to confirm the level switch changes in time.
- Pump and capacitor tests are done at live voltage behind panels, and a capacitor can hold charge.
- Rinse stage checks involve hot water and pressure in the boiler circuit.
- Separating a pump problem from a switch or board signal problem needs a meter and the wiring information.
Technical reference
- Document
- UPster U 400 M2 Glass- and dishwasher - Original operating instructions (type M001DWUC10M2-10)
- Edition
- 9760441 / Valid from: 2018-02 / Update: 2026-06
- Models / control
- Meiko UPster U 400 M2 glass and dishwasher, M001DWUC10M2-10
- Section
- 9.6.1 Messages: INFO table printed p. 33, ERR table pp. 34-35 (of 50)
- 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 MEIKO dish machine error codes
Can I keep washing with ERR 204?
No. The manual says it is not possible to continue working, and to call a service technician.
Is ERR 204 caused by dirty nozzles?
The manual does not list nozzles. We list scale in the rinse arms as a likely cause, so it is worth checking.
Why is ERR 204 different from ERR 203?
Both mean the boiler level switch did not change. ERR 204 is judged after the rinse time ends, ERR 203 while emptying.
Need help with MEIKO error code ERR 204?
A technician confirms the cause on site and gives you the price in writing before any work starts.