Can airtap ATI66 fill a large tub, if not, qhat is viable alternative

[Jon-Paul]

My client has a system running off of an airtap ATI66 amd cannot fill her large tub with hot water. How could I adapt something to make this work. Maybe an inline on-demand heater specifically for the tub? Any ideas or input would be greatly appreciated.

 

[ShaunCorbs]

Is it fully heating the store ?