Why does the ac smell bad
Could be the A/C drain is plugged and mold has started growing in the unit, as that is the most common cause, usually clearing the blockage and treating the unit with a good dose of Lysol thru the air intake of the A/C will take care of the bad odor but it will smell of Lysol for a while but that is better than the mold smell, as the A/C is used the mold will drop off as it is dead and will be washed out of the housing, so check the drain for a while to make sure it stays open. The other odor is if present can be a burnt wiring smell, this usually an indicating a blower motor or resistor block is getting ready too fail. HTH
Simply replace the climate control air filters for the evaporator and blower unit.
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