Tankless Water Heater Installation Safety
Recently we asked the head of one of the larger Commercial HVAC companies in northern New Jersey, whether they used a standard 3-way mixing valve when installing commercial tankless water heaters. “No, you don’t need one…” was his answer. His opinion is not uncommon. It is also dead wrong. As the technology of commercial Instantaneous Water Heaters and heat exchanger design improves, the use and number of installations of Instantaneous Water Heaters in commercial applications has grown. As a means to promote this technology many Commercial Instantaneous Water Heater manufacturers are attempting to sell this technology over tank-based water heaters by stating that an ASSE 1017 tempering valve (aka a 3-way mixing valve) is not required and that going tankless does not pose a health risk related to scalding or the growth of Legionella. It turns out that the science and biology of Legionella growth and transmission does not support that claim at all. Installer