You can refill Carbon Dioxide canisters at home and this site will provide you the required information. Just use the translation script shown on the page:
Carbon Dioxide bottles have the amount of CO2 contained displayed on it. The newer machines require 425 gram bottles while older machines require the 300 grams Sodastream bottles that are gray in color. You have to completely empty the bottle before keeping it in your freezer for some hours. After that procedure, just attach the smaller bottle to the larger bottle, place it on a weighing scale and fill it to its correct weight.
This will require a matching valve for the larger bottle and superior quality of rubber hoses with couplings that can work under high pressure. Even if you want to connect larger bottles to your machine directly, then you will still require the correct hoses and couplings. This will enable you to refill your bottles at home or even get them refilled at stores that refill fire extinguishers or even carbonic acid meant for pubs or for fish tanks.
Such couplings also make for a good business idea for make-your-own-wine-stores. You could also turn into a retailer for larger sized bottles or also for 2-4 kilogram refills. A higher-end CO2 pump can cost around 4300 Euros and cheaper ones cost around half. If you have such a pump, you could easily refill your customer’s carbon dioxide canister within 20 seconds flat. Leasing of refilling machines could help distribute the cost of such machines over a year or more and you could start your refilling business without investing a lot of money. However, prices of carbonic acid will not come down until manufacturers allow others to refill their bottles. AGA owns Wassermax and Airliquide that have their interests in different markets and are unlikely to allow others to stop their monopoly.
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But with the latest generation of soda machines now coming into the market with in-line carbonation features and inbuilt cooling systems, this ensures that carbon dioxide is not lost. This means that larger CO2 bottles weighing 2 to 7 kilograms can also be utilized. These innovations are sure to lure people towards buying such systems instead of opting for other flavored drinks.
These machines were actually meant to be used in restaurants but also work fine for home use. Machines without cooling systems will not remain in the market for long. Machines that feature cooling systems carbonate much better and even though they cost higher, the increased cost can get adjusted when you buy carbonic acid in larger bottles and end up with carbonated water that hardly costs a few cents per liter. You can also order from a wide range of flavors anywhere in the world from allfreightfree.com.