First off, there are multiple avenues to carbonate water at home. This is definitely one of the higher cost methods but once set up it's the least hassle. I don't have to buy expensive proprietary co2 cylinders or soda bottles (ie. Sodastream) and I don't have to refill and shake 2L bottles using carbacaps. Those are cheaper alternatives which I've used the latter of for the past 2 years. I had a supply of four 2L bottles of water always stocked in the fridge. I probably refilled them every 5-7 days and it was a noticeable chore since I had to shake every bottle.

Commercial Soda Carbonator

This project could be a bit over $400 US if you skip some of steps and buy used. I’ve used other people’s configuration as a jumping point while adding in my own ideas to best suit my needs. The centerpiece is the McCann’s Big Mac Carbonator that most commercial soda fountains use. Call with any questions 973-512-2028. The McCann Big Mac 'Ambient Temperature' Carbonator No. 5407 for High Usage (from 3 to 8 soda draft arms operating at one time).

Mccann Big Mac Carbonator Manual

This is my particular setup for an “unlimited” supply of seltzer water for a bit over $1000 Cdn to give you some inspiration to complete your own. This project could be a bit over $400 US if you skip some of steps and buy used. I’ve used other people’s configuration as a jumping point while adding in my own ideas to best suit my needs. The centerpiece is the McCann’s Big Mac Carbonator that most commercial soda fountains use. It starts with city water passing through a reverse osmosis (RO) system with a bar fridge housing the RO pressure tank and carbonator. The seltzer can then be dispensed through a beer faucet mounted on top of the fridge. This mix of residential and commercial equipment keeps costs relatively low and the space requirement to a minimum. The only maintenance I have to do is to change the RO filters at the recommended intervals, inspect the pump filter once a year and refill the CO2 tank roughly once every 12-24 months.