My question is no the merits of a recirc system, but can it deliver sufficient hot water to a high performance shower system needing 15+ gpm. What size/spec hot water heater is recomended? Any sugesstions would help.
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I don't know about recir systems, but a tankless water heater will keep up with that flow rate all day long.
Regards,
Scooter
"I may be drunk, but you're crazy, and I'll be sober tomorrow." WC Fields, "Its a Gift" 1934
Which tankless water heater(s) will provide hot water at 15 gpm?
Noritz has several models. They can also be daisy chained to increase capacity, so their capacity is unlimited.Regards, Scooter"I may be drunk, but you're crazy, and I'll be sober tomorrow." WC Fields, "Its a Gift" 1934
The existence of a recirculating system should have no effect on this except to save the fraction of a second it would take the hot water to get from the tank to the shower. (At 15 GPM, you wouldn't have much of a wait!) That said, even a 50-gal tank would be empty after about 5 minutes or less and I am wondering what is planned to make sure you can drain this deluge away? Sounds like a fire hose more than a shower. A 15 GPM shower kind of makes the water-saving toilet seem a bit, er, pointless?
Mike Hennessy
Pittsburgh, PA
Aggreed. I'm not concerned with water savings in this case and I'm no sure a recirc system is the way to go. I'm more concerned with delivering an adequate supply of hot water to the shower. Could one 75 gal. do the trick or 100 gal. or do I need tankless?
Do the math. How long is your longest shower? Will anyone else be doing anything else for the next hour, like clothes, dishes, washing their hands?I think only tankless or 2 80's would do the trick.Regards, Scooter"I may be drunk, but you're crazy, and I'll be sober tomorrow." WC Fields, "Its a Gift" 1934
With that much volume I would look into tankless. Also a waste water heat recovery system to temper the supply to the H2O heater. I think the term is GFX, for Gravity Flow heat eXchanger.
Garet