I am designing a house for myself and want to use a tankless hot water heater. The issue is I am going to be on LP gas and I want to have a recirculating loop. Id rather not consistently use gas to keep the loop hot all the time. and to put a wrench into things I also plan to use the Return loop to warm my hydronic towel loop in the master bathroom shower.
So this is my idea, I use a gas tankless water heater to feed the home during water consumption and use a electric tanked water heater to feed the recirculating loop using a pump when water is not being consumed. The pump will be set on a timer and use check valves to keep the flow of the water in the correct direction. I also plan to have all of my hot water lines insulated to keep the water hot as long as possible.
Im looking for input on this design and if it will work properly. any input is greatly appreciated.