There are a number of indications that show the carbonator is empty:
- When you press the carbonating button and don't see any gas going into the bottle of water.
- Even after repeated presses, you don't reach the 'buzzing' sound
- The carbonating button may stay down
- The carbonator splutters, indicating it has run out of CO2
If you need a new or spare cylinder, please visit Sodastream.com to order directly or find a retailer in your area.