I dont think this is a good idea but im looking for some feed back. There is a company that makes a filter for your outdoor condenser. It says that it wont restrict air flow. I think it will cause high amp draw on the condenser fan motor and you will still have to acid wash the coil. Do you think that this is something you could sell to a customer since i have never seen one on a unit? Do you think there reasoning for the filters is benifical or not .