looking for the right tankless
Hello all…
I’m looking to have a tankless natural gas water heater installed in a 3300 sq. ft townhouse. My plumber informed me that most of the models avalible have to be flued to the outside of the house, instead of into the chimney like the older one. He had installed a unit that could use a chimney some months ago, and is getting back to me on that particular unit. I’ve done some searching and haven’t found any info on this particular issue. Any ideas or directions I can go in? Other questions I have as well about this are, what about placement, sizing, and also what about the idea of point of use. This project is a home that I just bought and will be remodeling the entire house. All new plumbing as well as electric. I have not found any point of use units that will run a shower. I think it would be ideal to have multiple point of use heaters and only have to run a cold water line to each unit. Any thoughts?
What your plumber is telling you sounds correct. A lot of gas tankless water heaters, e.g. Rinnai, are designed with powered integrated intake/exhausts that draw and exhaust from a single outside point. This allows for better heat recovery and backdraft prevention. Another manufacturer, Rheem I think it was, simply drew in indoor air and exhausted it, but was recalled due to dust/clogging issues and carbon monoxide. Better to have a isolated outdoor air system, I think.
I would imagine the main problem with multiple point of use systems capable of supplying showers would be the expense, running gas lines and doing venting for each, and the complexity of so many heating systems. Proximity of the heater to the point of use does reduce lag time, however..
