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Restaurant options for domestic.
I service this one owner who has 3 steakhouses, he just recently inquired another restaurant.
He has an existing boiler with 6 zones valve. ( has 2 pumps in parallel, if one stops working he can isolate that pump and continue)
Piping and wiring looks like something from a taco training ( Webinar).
He also has a pretty decent flat plate HEX off the boiler for domestic water.
Also has a tm 50 from Takagi. To make the long story shorter the takagi and the HEX are by passing the storage tank and there using the storage tank water to mix the water down. ( it took me 1 1/2 hours to trace it in my head)
He wants to simplify everything. The Tankless is on its way out. I put a heat exchanger in for him to buy him time to think.
What do you think will get him more how water for money spent?
Option 1. Install two naviens and connect it properly to the storage tank. ( somehow use this flat plate hex exchanger in the equation since it exists.
Or maybe a navien boiler with an indirect feeding the storage tank at 150 degrees and mixing valve to 130 degree.
The other restaurant I put the navien in and he likes them .