Start with the much more common problem of a failed temperature blend door MOTOR/actuator.
Not only more common, but a whole lot less expensive
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Answercheck fan operation( fan on fan hi when does it blow?I had the same problem...it was the clutch on the a/c compressor. Need to get another compressor.
is compressor clutch turning when ac is on.
Bad clutch on compressor, unplug the wires from the AC compressor, replace fuse if doesnt blow fuse its in compressor, if blows then gounded wire
In general, as I don't know about Windstar, this can be a problem with the linkage or valve to the heater core. So if the heater core is stuck inline with the engine water jacket and not bypassed, then it is going to produce heat no matter what setting it is on. If the problem is the other way, where it is the cooling that is stuck, then there could be a short in the switch or wiring to the compressor's clutch. The clutch is solenoid-operated, and if the solenoid is getting power when it is not supposed to, then cooling will occur whether you want it or not. Now if you mean different temperatures coming out of different vents, then it is likely a vacuum actuator not working the blend door. It could be stuck, broken, or have a leak in its tubing.
1. You have a bad compressor or. 2. You have bad compressor clutch or. 3. You have electrical issues or. 4. You have a bad drier and expansion block.
Look at compressor when engine running-You should be able to see if compressor clutch is pulling in. Try with A/C on and then with A/C off to see difference
not enough a/c refrigerantA/c compressor not kicking in (fuse?)Failed temperature blend door motor/actuatorSee "Related Questions" below for more
AC Compressor has died and needs replacement. The compressor will not turn therefore building pressure in the low side.
If it blows warm air with the AC on,the compressor is not supplying the evaporator with high pressure liquid refrigerant. The compressor magnetic clutch relay may be bad, the fuse might have blown or the compressor itself has mechanical problems. I would start by seeing if the magnetic clutch is engaging when the AC is selected. If the clutch is not turning,check the relay and the fuse. You might have also lost the refrigerant charge through a leak in the evaporator,condensor,piping, high and/or low pressure lines There is a high/low pressure switch in this system.I believe it is on the passenger side of the evaporator. On my 04,you can see it. If this switch has failed, the compressor will not operate. Good luck.
Try the A/C relay. it is located under hood. in the relay box.
The compressor needs to be changed. There is no more pressure in it. It keeps working but only hot air is comes out.
it blows air