I just (inadvertantly) used a part load factor curve for my gas-fired WaterHeater:Mixed which produced VERY low efficiency. That got me thinking about what sort of curve is appropriate for a water heater....
I have a sense and some technical references for boiler part-load efficiency, but a water heater is a different piece of equipment in design and control. Can any of you point me toward a better understanding of water heater part load efficiency?