AC not capable of adequately cooling

[Patrick Henshaw]

Hi Team - small caveat : This is not actually about a rental property I own rather I am a tenant ( and on BP looking to get into real estate investing for myself and be the Landlord I would want to do business with:) 

Short and long the rental I am in does not cool adequately (3 floor older home with "over charged" AC system). We live in Northern Kentucky and for the last 10 days the AC has been running non-stop (24 hours per day - we have a NEST that tracks actual data) with an AVERAGE household temperature of 78 (the AC actually doesn't cool down to the anticipated 72 degrees). 

I pay energy costs and am wondering if I am within my rights as a renter 1)  take a portion of the energy costs out of my rent since a certified AC repair technician said the current AC system is not adequately cooling the house and 2) purchase an auxiliary AC unit (of reasonable cost ~$300, less than 1/4 of my rent)  and take that out of the monthly rent? 

One of the couple Kentucky landlord/rental statues I found to support my case is - KRS 383.590 http://krec.ky.gov/legal/Documents/Kentucky%20Land...

Any help or guidance or even a YOU ARE COMPLETELY WRONG YOU SHOULD PAY FOR EVERYTHING is welcomed!

Cheers,

Patrick