Blakeslee Commercial Dishwasher Error Code Z10: Break Tank High Level
Z10 ALARM SL8 - BREAK TANK HIGH LEVEL is the break tank high-level alarm. The manual says to contact Technical Service. A service technician should check the break tank level control and the supply to it.
Medium: a protective stop with possible overflow, but the cause is usually a level control.
- Code
- Z10
- Maker
- Blakeslee
- Equipment
- Dish machines
- Applies to
- D-18D / D-18V digital-control door-type
What does Blakeslee error code Z10 mean?
A break tank is a small holding tank that sits between the building water supply and the rinse system. It holds water at atmospheric pressure so that the rinse cannot siphon dirty water back into the supply. The control watches a high-level sensor in the tank, labeled SL8 in the alarm text. When water reaches the high mark, the control closes the supply and displays Z10 ALARM SL8 - BREAK TANK HIGH LEVEL. The manual lists it as a break tank high-level alarm with Contact Technical Service as the only instruction. A level sensor that is stuck, an inlet valve that does not shut or an outlet that is restricted can all keep the level high. The alarm is a protective stop: allowing the tank to overfill would spill water onto the floor and the machine's wiring.
Affected models and control systems
Blakeslee D-18D / D-18V digital-control hood-type dishwasher. The manual's cover prints D-19 L and D-19 LRS and names no D-18 model, so the alarm list is read as covering this hood-type family.
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
- Z10 ALARM SL8 - BREAK TANK HIGH LEVEL on the display
- Water running or dripping from the tank
- Machine will not fill or start
- Alarm stays after a restart
Possible causes
Likely causes — what usually sits behind error code Z10 on this control. A technician confirms which one it is before any part is replaced.
- Break tank inlet valve not closing at full level
- Level sensor SL8 stuck or fouled
- Outlet from the break tank restricted
- Level circuit wiring or board input reading high
Safe checks before calling for service
- Turn the machine off and look under and around it for water on the floor.
- Close the supply valve if water is still running.
- Wipe up any water so nobody slips.
- Do not remove panels or reach into the tank.
- Note whether you saw water overflowing or only the alarm.
How a technician diagnoses error code Z10
- Read the alarm record and confirm the Z10 / SL8 entry is active.
- Check the break tank inlet valve for leakage or a stuck diaphragm when it should be closed.
- Inspect the level sensor SL8 for scale, debris or a stuck float.
- Check the tank outlet and the lines leading to the rinse for restriction.
- Test the sensor circuit with a meter and replace the failed part.
- Break tank water sits close to line-voltage wiring and pumps.
- An overfilling tank can leak into the machine and onto the floor.
- The sensor, valve and board input have to be separated with a meter and the wiring diagram.
How error code Z10 differs from similar codes
Z10 is a supply-side high-level alarm. The B and E codes on this machine cover the boiler and wash tank.
Technical reference
- Maker documentation
- Blakeslee owner support
- Edition
- COD. 3100ET_U, Ed. 06 - 09/2018
- Models / control
- D-18D / D-18V digital-control door-type
- Section
- Chapter 8.2 Alarms, table 3 (p. 39)
- 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 Blakeslee dish machine error codes
What is a break tank?
It is a holding tank between the water supply and the rinse system that protects the supply from backflow.
Can I keep washing with Z10?
The control has stopped the fill for a reason. Check for water on the floor and wait for service.
Is SL8 a part I can clean?
SL8 is the level sensor in the alarm text. Cleaning it means opening the machine, which is a technician job.
Need help with Blakeslee error code Z10?
A technician confirms the cause on site and gives you the price in writing before any work starts.