Thanks. I've managed to find a few reviews, but not many, and they seem to vary a lot. I suspect some bad reviews (mostly older ones) may be due to indifferent maintenance.
I saw the Monitor name when looking for reviews. I found a website in CT that lists both. Almost identical! I wouldn't be surprised if Monitor are made by Toyotomi. Only Toyotomi are available out here.
I've heard a lot of good things about Rinnai
But in this case, I'm looking at non NG heaters for emerg. backup due to plans to outlaw NG here for primary heating in new construction. I currently have a NG condensing boiler & rads which I can run from my whole-house battery backup + diesel genny, as well as a pellet stove, but I'm thinking that, several years down the line, I may not want to schlep bags of pellets. Since I'll have the diesel genny anyway, a diesel heater might be a good option.
