BTU / Size for Aqua-Hot vs Hydro-Hot
Both are 50,000 BTU diesel-burner and have 1650 watt 120 volt AC electric heating elements. Both are available in 12 volt DC voltage systems but Aqua-Hot also offers 24 volt
They refer to Hydro-Hot as the “Little-Brother” of the Aqua-Hot because they both provide a continuous on-demand supply of hot water, have a 3-zone interior hydronic heating system and engine preheating, although with Hydro-hot it’s an option and not a factory feature. The Hydro-Hot can provide the same heating features as the Aqua-Hot, when there is a demand for continuous domestic hot water, the demand period for the interior heating system is put on standby mode.
So basically when it comes to servicing the Hydro Hot, it's the same as the Aqua Hot.