Hello,
As required by 7.4.2 Equipment Efficiency of ASHRAE 90.1-2007, for a water heater less than 12 kW and more that 20 gal, the required performance is EF=0.97-0.00132*V.
My question is: is there any other way to show compliance with this? Maybe with some other efficiency parameter or some good insulation value? Because I've been making some research and there are no companies that sell that product with that specification in my country (Peru).
Thanks in advance.