I just received the product, and haven't yet installed it. It appears to be well constructed, and it includes adapters for either compression or Pipe thread connections. But here's the rub: There's a big warning on the case, and a sealing sticker that the warranty will be void if the case is opened. Sounds like standard boilerplate, right? ...Until you realize that the mounting screws and plumbing connections are external, but the Electrical conections are internal. The description on the web seems to imply that a power cord is pre-installed, but the unit I received had no power cord, and just a female threaded hole on the bottom for a conduit connector. The actual electrical connections are inside the case, so there is NO WAY that it can be installed without breaking the seal and opening the case. So expect to file a lawsuit if you ever need to make a warranty claim. Hopefully, I will rely on the other good reviews for this unit and trust that I'll never need to do that... It's probably an excellent unit. I chose it because it is the smallest unit on the market that uses a modulating thermostat. I live alone in the country, on a private well, and the fixed on-off thermostat in the Atmor 6.3kw unit I tried drove me crazy with varying output temp as my well pump varied the pressure from 40 to 60psi. I have much better hopes for a comfortable shower without scalding or freezing surprises with this unit. It's also listed as having a .25 or .3 GPM cut-in flow, which is less than the .5gpm of the Atmor unit. I believe that was responsible for some of the chilling 60-degree surprises in the shower as well. So the bottom line is this: Insist on a modulating thermostat if your use case is a shower, or even a handwashing sink with a single-handle control. The simple on-off models would be fine for a non-human use like a dishwasher or washing machine, and probably manageable for kitchen or handwashing with dual-handle controls. But in my opinion, a single-handle control is incompatible with an on-off thermostat because output temp varies inversely with flow rate, so the use of a single-handle control is dangerously non-intuitive. UPDATE: Well, I've had it installed for a day now, and I've used it for a single glorious shower. The temp wasn't absolutely constant, but the variation was well within a safe, comfortable range. I have an energy monitoring datalogger on my electrical supply (OpenCMS), and a review of the energy use during my shower showed a clear repeated sawtooth pattern as the well pump kicked the pressure up to 60psi, then fell slowly to 40psi. The difference in flow was not obviously apparent in the shower, but clearly the sensors in the ecosmart unit responded quickly and appropriately to the changing conditions. There's one other grmbl I should mention. Not only are the electrical connections located inside the unit, so voiding the warranty is a necessary pre-condition to installing the unit, but the 'Earthing' Green screw is located UNDERNEATH the central thermostat control and display. Not only that, but it's much too small for the 8GA wire that the code requires in this area. I was forced to remove four additional screws so I could lay the thermostat assembly to the side to make the connections, and find a crimp-on fork connector for the wire. That was non-trivial in itself. It's not common to connect an 8GA wire to a #6 or #8 stud, so every one I had on hand was either too small for the wire, or too big for the stud. Is it too much to ask to design it with a three-terminal block instead of a two-terminal block and a tiny hidden screw? How much would that cut into your profit margin? Back to the plus side... The internal plumbing parts appear to be stainless steel, and the inlet and outlet temp sensors are actually inside the water flow. That's probably responsible for the fast response and small variation in temp control. On the other unit, the internal parts were plastic, and the single temp sensor was just zip-tied to the outside of the heater chamber. The insulation value and thermal mass of that plastic I'm sure contributed to the wide temp swings and scalding surprises. Bottom line: This EcoSmart 8 appears to be mostly well designed and constructed, so I'm expecting a good service life from it. It was the only model I could find that has a modulating thermostat and would run on a single 40Amp breaker. (Did I mention I live in a mobile home with a 50Amp main supply?) Oh, one other thing: Both inlet and outlet connectors are near the top of the case, and there is no gravity drain provided at the bottom. So avoid this unit if your use case is a seasonal summer home and you need to drain in the fall for winter freeze protection. With this unit, you'd need to use an air compressor to blow out the unit, and even then, it would only be effective if you applied the air pressure backwards, from the outlet side.
