Can you clever folks tell me about this one? My husband did an excellent job installing our tankless water heater. I was out of town that weekend, but given his record for thoroughness, handiness with tools, & researching how exactly to do something right, I believe he put it all in right. It is this one right here: http://www.hotwaterheater.com/model-h-28-4.htm
However, now I can't get a hot shower!! I had nice long hot showers with the tank system, but now, nope!! It starts off and builds up to scalding water pretty quickly, if I crank it all the way up. Then I push it back down to the correct temperature. But then it quickly tapers off after a minute or two, and the rest of the shower is lukewarm! It will get a little hotter & then colder in turns, which is also annoying; but never gets hot, even if I push it all the way back to the maximum. It's definitely not a comfortable showering temperature, even.