Meiko UPster U 400 M2 Error Code ERR 305: Boiler Fills Not Enough
ERR 305 on a Meiko UPster U 400 M2 means the number of boiler fills was not enough for rinsing, so tank level 2 was not reached. Check the water supply valve and hose, then clean the inlet filter and the rinse nozzles. If ERR 305 shows again, call us.
Medium: the rinse boiler does not fill properly, which limits rinsing.
- Code
- ERR 305
- Maker
- MEIKO
- Equipment
- Dish machines
- Applies to
- UPster U 400 M2
What does MEIKO error code ERR 305 mean?
The final rinse on the UPster U 400 M2 uses fresh hot water from a small boiler, and the control fills that boiler in a number of steps, checking the level each time. ERR 305 appears when those fills were not enough to bring the water up to level 2, the mark the rinse needs. In other words, the rinse water boiler is not filling the way it should. Most of the likely causes are on the way in: a valve that is not fully open, a kinked or pinched hose, an inlet filter blocked with sediment, or rinse nozzles clogged with scale. Those all limit how much water reaches the boiler in the time allowed. The last possibility is the boiler fill valve itself, or the level sensing that reports the result. The manual's operator steps are to check the water supply, the hose, the filter and the nozzles, and to call a technician if the message returns. Handling wash parts means working near detergent, so wear the gloves the chemical maker calls for.
Affected models and control systems
This is for the Meiko UPster U 400 M2 glass and dishwasher. Other Meiko models use different numbers for rinse boiler messages.
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 305 on the display
- Final rinse that is weak or missing
- Slow filling noise at the boiler
- Glasses coming out with soap film
Possible causes
Listed in MEIKO's documentation
- Water supply and the hose
- Filter clogged
- Nozzles clogged
- Boiler fill valve and level sensing
Other likely causes — what usually sits behind error code ERR 305 on this control. A technician confirms which one it is before any part is replaced.
- Supply valve partly closed after cleaning under the counter
- Fine sediment in the inlet filter after work on the water main
- Boiler fill valve coil weak, so it opens slowly
Safe checks before calling for service
- Check the water supply valve and the hose.
- Clean the inlet filter and the rinse nozzles, as the maker says.
- Wear the gloves the chemical maker calls for when you handle wash parts.
- Restart and listen for the boiler filling.
- If ERR 305 shows again, tell us how often and call us.
How a technician diagnoses error code ERR 305
- Read ERR 305 and check supply pressure and flow.
- Inspect the inlet filter and the fill valve.
- Test the fill valve coil and measure fill time.
- Check the boiler level sensing against the actual level.
- Inspect the rinse nozzles for scale.
- Replace the valve or sensor only after the tests.
- Testing the boiler fill valve coil means meter work on live control wiring.
- The rinse boiler holds hot pressurized water that can scald if it is opened.
- Judging the boiler level reading needs the machine's own readout during a fill.
How error code ERR 305 differs from similar codes
ERR 301 is the wash tank failing to fill, while ERR 305 is the rinse boiler.
Technical reference
- Document
- UPster U 400 M2 Original operating instructions 9760441 (update 2026-06), 9.6.1 Messages p.33-35
- Edition
- 9760441 / Valid from: 2018-02 / Update: 2026-06
- Models / control
- UPster U 400 M2
- 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 305?
The rinse needs this water, so results will suffer. It is best to stop until it is fixed.
Is ERR 305 a heating problem?
No. It is about filling the boiler, not heating it.
Will cleaning the filter fix it?
Often, if sediment was the cause. If not, call us.
Need help with MEIKO error code ERR 305?
A technician confirms the cause on site and gives you the price in writing before any work starts.