✅ If buttons don’t respond, lock mode is ON. Hold the lock icon for 3 seconds. Not in the manual? Barely.
✅ “No water” light flashing but tank is full? Remove, reseat, and push down firmly. The valve needs a solid click. viomi 4l water dispenser manual
✅ Use citric acid (not vinegar) for descaling – vinegar can linger in taste. Run a full tank with 1 tbsp citric acid, rinse twice. ✅ If buttons don’t respond, lock mode is ON
