This is definitely air conditioner weather.
I had a customer in here last year with his a/c not putting out cold air.
I raised the hood, that always helps, and looked at the compression. The clutch wasn't turning.
I disconnected the switch at the low pressure cut- off valve and took a bent paperclip, in the shape of a horse shoe, or a "U" for those of you that never bought your horse any shoes.
I inserted both ends into the slots in the plug, and, wooden, the compressor clutch started turning.
I hooked the gauges to the a/c lines and opened the valves to read the pressure.
Pressure was fine.
I replaced the low pressure cut-off valve and the a/c cooled the vents inside the truck down to 39o.
The customer looked at me rather oddly and said, "I had it checked last week and they wanted $1200 to make it get cold."
I hope they were just giving him an estimate for a complete rebuild job, just in case it needed it.
Tommy Sessions has been in auto repair since 1970. He publishes Bad Car Again Auto Repair Help Newsletter. Visit the site: http://www.badcaragain.com Join: http://www.badcaragain.com/newsletter.html There's a bonus just for joining. Take Care Of Your Car So It Can Take Care Of You!