Andy,

The best I can say is "maybe."

See 220-15, the exception seems to offer some wiggle room. If all units will be on at the same time, what about the lights & receptacle load, are they on another feeder? Seems to me that there is not enough capacity. To apply the exception, you'll need permission from the AHJ.

Tom

Few things are harder to put up with than the annoyance of a good example.