I’m a helper and worked with an old time electrician and he did something a year ago that still troubles me. We wired a 50 amp 220 volt circuit for some heat pumps. he brought the wires into the panel, hooked them to ground and the breaker and left the white wire capped with a wire nut. He told me it will work fine and forget about it. Did we leave somebody with an open neutral? Is the ground wire the neutral now? Should I try and go back and fix this?
If the equipment in question doesn’t require a neutral (like much HVAC equipment), then the neutral isn’t floating, it just isn’t used/terminated on either side. I’m assuming you guys pulled in 6/3 or 8/3 romex, both of which have a #10 ground. Personally, I would have tied down the neutral in the panel side, but it isn’t a big deal, it’s just an unused wire at that point.
Remember that with 240v, you have 240v of potential difference between the two opposing 120v phase legs, and the opposition of phases are what complete the circuit all the way back to the transformer.