1999 Stratus Air Conditioner Hot air at idle

My 1999 Doded Stratus Air Conditioner works fine when I am going down the road, but it does not work at idle. Is there a switch or relay that may be bad causing the compressor to kick off at idle. Could it be low on Freon.
It cools fine when the car is moving down the road.
Thanks for any help.
DonD

Low freon sounds like the problem. You can pick up a refill kit at any auto parts store and re-fill it yourself.

Since it works except at idle, 1 14 oz. can should do the trick.

Thanks, I bought a can of freon with hose and gauge form Pep Boys for $15.00 and it works fine. Hose and Gauge is reusable, so next time only a can of freon.
Thanks again;
DonD