I have a few problems all started at the same time. A/C does not blow cold air, when car is cold it makes a loud screeching sound when the defrost fan is turned up. Power steering is sometimes very hard (tough to turn steering wheel). Can any of this be related? Someone suggested the serpentine belt needed replacing? Also, I replaced my windshield recently and now the intermittent sensor doesn't work. I have the sensored wipers and have been through this before where the technician doesn't recalibrate the sensor. Is this why the intermittent setting isn't working now?
You have several possible isssues going on. The hot A/C could be from an improper level of r-134a refrigerant. You need to have that checked by a repair shop and have the refrigerent pressure checked or just get it flushed and filled.
The loud screedhing could be the air door for the defrost not clsoing all they way and creating a small gap that squeals when air passes by. It might also be the blower motor going bad.
The power steering pump sounds like it is going bad. Check the fluid level and then grab the pulley and check for play. If there is play you need to replace the pump or if the fluid looks or smells burnt.
The intermitant snesor is generally set by a control board. You may have a problem with the control board or the multi-funtion switch for the wipers.