I have a single phase 238-240v air handler with 15 kw(3 - 5kw strips) of heat strips. I want to wire this with 3 ph 208 wye. Can I change the wiring to this: L1 ~~~H1~~~L2 / L3 ~~~H2~~~L1 / L2~~~H3~~~L3. Then send L1 & L2 to the 240 system fan for a single phase fan motor. This Should give me a load of approx 50 amps per phase with an additional 4 amp load from the fam motor on L1 and L2. I planned to use a triple pole 60 amp for the service. Is this right? Will this work not having 3 phase heater coils? Please advise.

There is no such thing as a 3 phase heater, they will always be three single phase heat elements connected in a Delta fashion, see diagram.

How to wire the 9 coils of heating furnace carring 65A current . If it connect in delta fasion where to connect neutral wire, Is it necessory to connect neutral wire coming from transformer?
I have the problem that when one of the phase get dissconnect neutral wire carring current . How I wire these 9 coils using neutral ?

Exactly what type of delta system do you have?

I connect it in star i.e. end of the cois goes to neutral of transformer