Hi Tom,
    Well, if you could swap out the power supply that would be the easiest . 
If you don't have a spare one you may be able to find a loner.
    The next thing I would try is putting ferrite beads on all wiring that 
comes out of the air-conditioner.
    A third idea is that some VHF or higher harmonic might be getting in to 
the unit. So, you might try a low pass filter between the rig and the 
antenna tuner.
    That's all my thoughts for now.
                    God bless,
                    mark WZ0K
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