There should be appx 15*-20* difference between return and supply air temps measured at the unit (not the registers).
This usually happens because the AC is set to heat and not cool. If it is set to cool then get it checked out by a qualified AC technician.
The freon either needs to be charged which can be done at a local repair shop about $50 - $85 or the the A/C compressor which can cost upwards of $500. Also check for simple leaks or stains under...
Low refrigerant charge? Temperature control cable not adjusted properly?
Get it service by A/C Tech... You may have a leak or broken hose.
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