Tankless water heaters do not meet expectations
by Maurice Branzanti
(Todos Santos, BCS, Mexico)
All the talk about tankless water heater that I have found so far, is about their efficiency, their unlimited hot water,their savings: save money and energy, save space, save water, etc. etc. All things that I really do not care.
What I really care is having a heater that can supply temperature controlled water when I needed, and for this, tankless water heater simply DO NOT WORK. In the past two years I have replaced 5 units, (the Bosch make, propane fueled, the only available where I am), all with the same problem. After installation and having followed all the manufactured procedures, my showers are either scalding hot or freezing cold, nothing in between.
The reasons? It just so happens that the propane flow valve, is controlled by a water flow/pressure sensing unit with a very narrow window of operation. You turn ON the hot water, water flows hot, you add the cold and there your hot water is gone. The propane valve has shut OFF. I have 3/4" pipes that allow unrestricted flow and have plenty of pressure. These units just won’t work.