On Wed, 4 Dec 2019 09:22:37 -0600, dpb wrote:

On 12/4/2019 8:30 AM, trader_4 wrote:
...

A 240V breaker sits across both hot legs. I doubt it's code compliant
to use just half of it for a 120V circuit, but IDK. Fretwell?

Isn't. No dedicated neutral to the circuit that way.

Only (used to be but even it isn't allowed any more) was the 3-wire
service for dryer-like appliances with the ground serving as secondary
110V circuit neutral. That now requires 4-wire, not just three.

A range or dryer is assumed to be a 120/240 load and needs a neutral
but if the equipment is 240 only, it is not required to have a
neutral. (no 120v load).