What fuse is for the Air conditioning? I have a 96 Saturn SL1. My AC is blowing hot air. My husband charged it, but to no avail. The pressure increased a little.

It sounds like vacuum is not getting to the vent, heat and A/C controls. Find the vacuum can. It may be under the hood on one of the inner fenders. The "one-way" check valve is usually located in the line and close to the can, make sure it works properly. The valve could be the very thing that's causing the problem. Trace the lines back to the vacuum block at the intake manifold or fire-wall, and also back to where the line goes thru the fire-wall. Check the can for leaks or obvious holes. They used to be just a plain metal can, but it could be a plastic ball. Check the lines as you go, for breaks and rub-thru's. Move the controls thru all settings and listen for vent door movement. Worst case is a bad vacuum motor or air flow position selector switch, and/or a faulty Blend Door Actuator. If you have been driving around with the Temperature knob or control set at the same spot for months, move it from fully cold to fully hot several times and wait for the air temperature to change each time. This will help reset the blend door and vacuum control system. Hope this helps... Let me know what you find.