A/C always enabled.

[Michael Cacioppo]

I've noticed that regardless of what position the heater/AC knob is in (except OFF) the A/C clutch is enabled and an A/C load can be present even on straight heat setting. I'm familiar with cars having the A/C enabled when in defrost mode, but never in straight heat. I pulled the 10 Amp A/C clutch fuse to disable the A/C from coming on. Do others have the same condition? I will let you know if gas mileage goes up, it should. A performance increase is noticed already.

 

[Frank Marano]

i did this when I had my 99 rodeo. I didnt notice any difference in mpg but of course the a/c didnt come on. I also think it hinders the defrost in some way......I am not exactly sure though....:lol:

 

[Chris Taylor]

My '03 does not run the compressor when on straight heat(2 marks to the right from off), panel(one notch to the left from off) or off itself. All the other settings, the AC is active.

 

[Adam Yee]

my A/C does the same as ChrisT's... is this normal? I always noticed that my "cold" temp in the summers was like having a/c even tho i didn't think it was on... I always run my setting on the second last setting to the right.. does that mean my a/c is running in that position too even when the heat is on? is this normal?

 

[Michael Cacioppo]

Chris, I double checked. Mine works the same way. I assumed that upper/lower was staright heat also. A/C is OFF in heat lower only ( 1 to the left of OFF) and heat upper only (two to the right of OFF). A/C is on with upper/lower heat setting (1 to right of off). It seems strange to put A/C on with upper/lower heat setting. That is not a defrost setting and I would assume should have been made A/C off also.



Thanks for the replies.

 

[Jeff Harwanko]

I believe that the A/C compressor should run as needed (on and off) in all positions except to floor only and off. The system uses the A/C to remove humidity from the air. If it is running in all postions it may be that the Compressor Clutch has locked up and is not allowing the compressor to "free wheel" when not being used.

 

[shawn stonbraker 2]

I agree with CE Trac. Mine kicks off and on in curtain settings. If yours isn't shutting off I'd get it checked.

 

[Michael Cacioppo]

Scott, I did not see that in my '03 manual. BTW what is the logic for it being on in the " floor + vent" mode?

 

[Chris H]

The compressor dries the air as it cools it, right. Cold air does not hold very much moisture, but will hold enough to de fog a window if it is dried. Hot air hold a lot more moisture. So in cold winters blowing heated outside air does defog the window with out the need to dry( condition) it. (Physics lesson)



So doesn't a blend damper cut off flow through the AC coils when you have it on heat setting? Aren't we running the AC with little to no air flow?



My Volvo is the same as my ST. Must be a Ford thing.

 

[Tom Schindler]

We had a Dodge Caravan where I used to work. It had a seperate on/off switch for the AC.



Guess what, the AC run whenever you had it on defrost or anything that blows air to the windshield. It did not matter if the switch was on or off.



I guess it must actually be a car thing.





Tom

 

[Michael Cacioppo]

Chris, I understand the physics. The upper + lower switch position does not blow air on the windshield. It is just venting through the dash and the floor.

 

[Fer Echegaray]

I've always thought that it should have a separate on/off switch...