The only difference between a 208v and 240v, 3-phase oven is the elements. An oven with 240v elements in it will work fine on 208v – with exception to a 13% reduction in heat producing capability. That’s normally NOT an issue – except for slightly diminishing the oven’s ability to recover when the oven is heavily loaded.
If you still insist on putting 208v elements in that oven, here’s the element you’d order for it:
The parts manual for that oven is kooked up. It shows part numbers for contactors rated to each voltage, but the part number for a 240v contactor doesn’t cross to a contactor at all. It crosses to a natural gas control assembly:
Notice that Ptown also list the part as being for 4 different electric ovens. Wonder how that conducts and controls electricity.
I was surprised that they don’t have a low voltage transformer. most times they have to be changed or reconfigured. I also have never come across 240V 3 phase. 230 is a delta system 3 phase. And 208, 440, and 580 are common. I’m thinking it must be single phase to be 240 Volt. Think I would want to look at the terminal block.