Rep Power: 0

Here is the deal. My mechanic replaced the thermal switch, fixed a loose connection and evacuated and recharged coolant. But we have a new problem the A/C will work and blow freezing cold air when I get in the car to go to work. After work the air is not cooling. Air is blowing but not cooling. This is happening everyday! Does anyone know why?

 
Rep Power: 352

did u actually turn the AC power on? and not jsut the fan?

do u live in a place where the temp outside changes drastically? cuz in the morning (here in palm springs) its like 80 degrees and in the afternoon its 116+ degrees. makes a difference.

 
Rep Power: 0

He probably overcharged the system, take it back when its hotter outside and ask him to check the pressure of the system, it should never get above 55 psi. when it does the system shuts off to save the compressor. If he overcharged it all he'll have to do is remove some of the charge.

 
Rep Power: 0

Are you saying that it stops cooling by the time you get to work, or stops cooling when you get back in the car after you've been to work?

Assuming you have a thermostat switch, or thermo switch (aka thermal switch haha), I will assume you have a TXV system (thermostat expansion valve rather than a FOT system).

If it works right until you get to work and then stops right before you get there, your thermo switch is not working properly (even though you said your mechanic changed it, it could be another faulty switch). Your thermo switch is used to duty cycle your compressor to prevent evap freeze up and have the coldest air possible. If your thermo switch was not telling your compressor to turn off, the moisture around your evaporator will turn into ice and stop air flow (an evaporator is a mini radiator like guy, who carries low pressure cold liquid though tubing). This would explain why it works sometimes and not others. How long is your ride to work?

Another possibility is a hot water control valve. On some cars (not sure if it's on yours or not) instead of using a blend-door they use this water control valve. This means the cold air you love so much crosses the heater core (mini radiator used for keeping you nice and warm when its cold out lol). If your hot water control valve decided to stay open when it was supposed to be close your cold air would have no chance of making it to the cabin. The heat way over powers the cold.

So that's just two possibilities but let me know any other details you have and I may be able to better locate the problem.