tankless hot water heaters with recirculation
Looking at possibly going tankless, but, there are considerations. The home is 5.5 baths and has a dedicated hot water recirculation line. I've looked over a couple tankless heaters (Rheem and Navien), and one of them, the Navien, has what looks like a recirculation pump built in? Navien NR240A. I'm not sure how this works with a recirculation line. I thought the benefit of a tankless system was that when there was no demand, there was no gas being used. With a recirculation line, wouldn't the hot water heater be on whenever the recirculation pump is on? Thus negating it's efficiency to some degree? I understand that the pump could be on a timer, so on off hours the recirc pump could be off, so saving some energy there. Because the home has a recirculation return line is one of the big reasons I was considering NOT to get a tankless.
Any thoughts are welcome. Thanks!