I tore into it some more and it turns out that the inlet valve had it's knob broken off and the valve itself was in the closed position. I fixed that and now it fills and heats up but I've still got no flow out of the group. The pump seems to be trying to work, though. It turns on and I see several amp jump in current pull.
I think you're right, Larry. It's wired for 110v, though I can't tell for certain as the data plate is illegible.