This is a topic that is near and dear to my heart. Why do so many people hate tankless? Whether I am speaking to another contractor or a homeowner the reasons given seem to be that they do not work. Bull sh**, at John Baethke & Son Plumbing we service every major brand of tankless water heater and almost 100% of the time when a customer calls us that they have an issue with their tankless it is not the tankless. Almost without fail when we go on a service call for tankless it is an improper installation. There are so many things that you can screw up when you install a tankless. For starters a tankless water heater uses about 5 times more gas when it is working than your standard heater. Just this fact means that you had better increase the gas pipe size substantially. Funny thing is many people get this part right. The next concern is the size of the homes gas meter. Typically the meter is sized to allow between 250,000 and 270,000 btu's of gas flow. That was fine when you had a 100,000 btu furnace, a 40,000 btu water heater, a 30,000 btu dryer and a 30,000 btu stove. Now a days the stove alone can draw over 100,000 btu's. So lets add up a modern home with a tankless. Your average tankless is 199,000 btu's, furnace 100,000 btu's, dryer 30,000 btu's and a high-end stove and cook top can easily be 150,000 btu's. That totals 479,000 btu's, guess what? Your meter is too small. We see this almost every day! We can add to the mix the fact that most tankless' are also vented incorrectly, do not have service valves, and are not installed in the most appropriate circumstances and now you can understand why so many people hate tankless. The problem started when Bosch corporation first put their heaters into the Home Depot stores. Every Tom Dick and Harry thought what a great idea it would be to have a tankless so they bought one. unfortunately the last thing they thought of was hiring a professional to install it. Most of those original heaters were installed by either the homeowners, handymen, or heating companies, and the vast majority were screwed up. That gave Bosch a very bad reputation. That was very undeserved. The heaters were not the problem, it was the installation. So, if you want a tankless water heater, start by hiring a professional to install it and you will be guaranteed to have many, many years of great hot water and trouble-free service, we guarantee it!