Not the correct part

I could see doing this for the short time it took to drive and get the correct contactor if it was extremely hot out side and one was trying to get the building cooled down but to leave it this way could get someone hurt if not paying attention

Charlie can you describe what you see as the problem (besides the white ungrounded conductors)? Is this 1Ø or 3Ø?

Sorry I should have said 3 Ph

I think that it might be somewhat common for a manufacturer to use a 1Ø, 2 pole contactor to control a 3Ø unit.

Yeah you can control it with a single pole but it leaves a hot leg on the compressor. They also use a single pole contactor with only breaking one leg, just a cheap way to catch someone sleeping. I always like to break both legs on a single phase and wire the crank case heater to the L side of the contactor. I guess I am just old fashioned