Eversys Coffee Machine Error Code W-022: Bottom Piston Failure
W-022 reports a bottom piston failure in the brewing unit. The machine tries to unblock it automatically, so let it finish first. If W-022 returns, stop using the machine and call us.
Medium: a warning that can clear, but repeats can lead to a blocked brewing unit.
- Code
- W-022
- Maker
- Eversys
- Equipment
- Super-automatic coffee
- Applies to
- Cameo (W-xxx warning messages)
What does Eversys error code W-022 mean?
The bottom piston in the brewing unit lifts the coffee bed into the brewing position and pushes the used puck out afterward. The control watches whether the piston reaches each position. If it does not move as it should, the control logs a bottom piston failure and shows W-022. Before it gives up, the machine tries to unblock the piston by itself, and coffee drinks may be delayed in the meantime. A light jam may clear itself, while a repeat points to wear or a build-up. Grounds and coffee oil collect around the bottom piston more than elsewhere, because the puck is pushed out over it. The message names the bottom piston only, not the cause, so a technician looks at the piston, its motor and its supply. A weakened motor, a worn seal or hardened grounds can each hold it back. Staff should not interrupt the automatic attempt, and they should not reach into the unit, which is moved by a motor. Emptying a nearly full grounds drawer is a safe step. W-022 sits beside W-020 for the top piston and S-020 when the unit is blocked entirely. The display text is W-022.
Affected models and control systems
This applies to the Eversys Cameo with W-xxx warning messages. W-020 is the top piston counterpart.
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
- Coffee drinks are delayed
- Warning on the display
- Machine repeats a movement before brewing
- Used puck not ejected cleanly
Possible causes
Listed in Eversys's documentation
- Bottom piston stuck in the brewing unit
- Grounds or oil build-up around the piston
- Piston motor or its supply failing
- Automatic unblock attempt not succeeding
Other likely causes — what usually sits behind error code W-022 on this control. A technician confirms which one it is before any part is replaced.
- A puck ejection path where oily grounds have packed along the piston edge
- A worn piston seal that leaks coffee into the guide and slows the stroke
Safe checks before calling for service
- Let the machine finish its automatic attempt before doing anything else.
- Empty the grounds drawer if it is nearly full and seat it again.
- Watch whether coffee drinks go back to normal.
- If W-022 returns, stop using the machine and call us, and tell us how many times it appeared in a shift.
How a technician diagnoses error code W-022
- Read the message history for W-020, W-011 or S-020.
- Power down and inspect the bottom piston and the ejection path.
- Turn the unit by hand where possible and feel for binding.
- Measure the motor current and supply.
- Clean grounds and oil and check the seal.
- Replace the seal or motor only after it fails the test.
- The brewing unit's pistons are motor-driven, and a hand inside can be crushed.
- The bottom piston sits under the puck ejection path, which takes the unit out to clean and inspect.
- Seals and motor are checked with a current reading and the power isolated.
Technical reference
- Document
- Eversys eSupport: Operator warning messages for Cameo (W-XXX)
- Models / control
- Cameo (W-xxx warning messages)
- Section
- Web page table of W-numbers, Infos messages and Explanations / Remedies (no page numbers)
- 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 Eversys super-automatic coffee error codes
Is it safe to keep brewing after W-022?
If it cleared and drinks run normally, yes for now. If it repeats, stop and call us.
What does the machine do on its own?
It tries to unblock the piston automatically, so wait for that attempt to end.
Is W-022 the same as W-011?
No. W-011 is the unit failing to initialize. W-022 names the bottom piston's movement.
Need help with Eversys error code W-022?
A technician confirms the cause on site and gives you the price in writing before any work starts.