First, narrow it down
Dry the outside of the gun with a clean towel. Press and release one button at a time, then see whether liquid appears at the nozzle, under the button plate, or near the bottom of the handle.
What you're seeing
| Symptom | Possible cause | What to do next |
|---|---|---|
| From nozzle | Cork O-ring or molded valve | Record flavor and model; valve service. |
| Under button plate when pressed | Stem O-ring | Identify affected button; stem seal service. |
| Around bottom plate | Hat O-ring | Bottom seal service. |
What to check
Dripping from the nozzle after you release the button
A worn cork O-ring on older models, or the molded valve on newer assemblies, can fail to seal. Note which flavor drips and whether it is a slow drip or a continuous pour.
Oozing under the button plate while you press
The stem O-ring for that particular flavor, soda, or water circuit may be worn. This is a distinct repair from a nozzle leak.
Liquid around the bottom of the handle
The hat O-ring at the bottom plate may be failing. Avoid opening the lower manifold while lines are pressurized.
Buttons hard to release or liquid continues flowing
A sticking button, overly tight butterfly retainer, or debris at the sealing surface can cause a free pour. Do not jam tools under the button to stop it.
Clean only the outside and approved removable nozzle
Remove visible sticky residue with the food-safe cleaning method for your model. Do not use a high-pressure spray or soak the handle, which contains the valve assembly.
Record gun model and leak location
Wunder-Bar publishes separate replacement procedures for stem O-rings, hat O-rings, and molded valves. The right part depends on the gun version.
Why it happens
The gun has several seals in different places. A leak under a pressed button and a leak through the nozzle are not the same failure, even though both leave syrup on the bar.
Need service?
Contact Carbonator for the correct seal or valve repair. Isolate a continuously leaking gun only using your approved shutoff procedure.
Contact us (215) 726-8000