A couple of issues here.......... 1) 29 sounds more like amps and not Volts. 2) if the amps are high at 29 amps that generally indicates that the compressor may be overloaded. There are several reasons for overloading of the compressor. It could be overcharged, this is common from fly by night AC repairmen they take advantage of consumers because there is not really a good way for the customer to know what the refrigerant levels/temps/pressures should be. Another potential problem is a dirty condensor not allowing the refirgerant to cool and condense in the outside unit. Lastly the inside unit could be dirty causing freezing conditions in the evaporator (inside unit) thus causing the compressor to work harder inturn causing more amps...... Now with all that said, the compressor has no impact on over VOLTAGE, this is something that is controled by the local power company... Hope this helps....

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