I have been doing a lot of work for a national seafood chain lately. The restaurants always run out of hot water because they run hot water for hours to thaw stuff out. Most of the heaters are A.O. Smith BTR 500's. I end up adding a BTR 365. The mechanical rooms are usually way too small, with two big heaters and a water softener and brine tank. They won't go tankless, can anybody suggest a boiler set up that they have done?