Hello,

I am trying to model a standard boiler vs tankless water heater for the same building. In the detailed edit water side HVAC, I have changed the tank volume to 2 gal, however, I am unsure on how to calculate heat input ratio (since the burner capacity and heat input capacity have to in same units but what units?), nor am I able to find anything on the burner capacity in btu/h for a gas fueled tankless hot water heater. Any information on these issues would be greatly appreciated.

Arslan