Could be the univolt or it could be poor / corroded connections between the source and the univolt.
What is the voltage where the A/S is pluged in ?
If you have a voltage drop between the source and the univolt then you have a resitive connection ie 120 VAC at the source and 116 VAC at the input to univolt the problem is most likely before the univolt if no drop in ACV the univolt should work ok at 116 VAC and the problem would be in the univolt.
Don't rule out a faulty braker or your test meter.
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