prob with climate control

[nascar_fan28]

ok. i have a 05 f350 xlt. my truck is blowing hot hot air. pretty much the problem is, i think its stuck on the hot setting, when i spin the knob to blue it still blows very hot air when truck is at operating temp. it switches from vent to floor to defrost no problem , but cant change the temp. even when i go to ac and max ac it still blow really hot air. i think it maybe a switch or maybe a fuse? is their a fuse. i seen in the panel a climate control fuse. didnt check it. anyone have this issue? thanks

 

[atvrider93]

doubt its the fuse cause then nothing would happen. can you shut of the whole air system? my moms mercedes did this on one vent only until we replaced some valve in the system, dont remember exactly what it is but I can find out

 

[DaveBen]

Can you switch to heat, vent, and defrost properly? Does the air move to the proper channels when you switch - or - does it stay on defrost? If it does stay on defrost, you have a vacuum leak. It is probably at the hubs. Common problem.

Dave

 

[BIG JOE]

Can you switch to heat, vent, and defrost properly? Does the air move to the proper channels when you switch - or - does it stay on defrost? If it does stay on defrost, you have a vacuum leak. It is probably at the hubs. Common problem.

Dave

I'd Second that.

Joe

 

[Tail_Gunner]

--- it switches from vent to floor to defrost no problem , but cant change the temp. even when i go to ac and max ac it still blow really hot air. i think it maybe a switch or maybe a fuse? is their a fuse. i seen in the panel a climate control fuse. didnt check it. anyone have this issue? thanks

If you're changing between the vents OK, then it's not a vacume source issue.

I don't think it is an electrical issue either since all the air routing, including hot vs cold is done via flapper doors that are operated by vacume actuators.

My first impression is you have either a bad temp control switch, a disconnected hose going to the vacume actuator or the actuator on the hot/cold flapper door itself is bad.

p.s. you might have some sort of foriegn object keeping the flapper door from going to the full cold position.

 

[nascar_fan28]

sorry for not getting back with you guys, i really appreciate all the help. i pulled dash and no loose connections on the switch. i guess i could find where the lines go on the switch and see if its connected. and ill try to locate where the doors to switch from hot and cold are. its pretty rough trying to defrost when its raining, and its blasting me with the hottest of the hot air haha. also i had a light go out on my dash, its one that lights up bottom left corner which is the fuel gauge and oil

 

[BigSilverHD]

Im not sure if the 05 is the same as the 99 but i am having that trouble as well. I found that there is a motor (electric) on top of where the blend door is at that operates the blend door. I found that was the problem and not actually the knob, with mine it still works but it gets stuck. If i help it while the knob is on blue it it moves just fine. so in all check that motor if its the same setup. hope this helps

 

[nascar_fan28]

it was the motor for blend door.. thanks guys