A/C freezes up?

[Dieseldumb]

I've noticed on 3 or more occasions that the air flow from the registers becomes greatly reduced(cab warms up); and, upon stopping and looking under the hood, that the air canister and refrigerant lines were iced up. Took it in under warranty and got my usual "nothing wrong answer" and that it was normal for unit to ice up in humid areas. I had mentioned that they might check out the Fin Temp Sensor(from previous posts for 2003 models) but they wouldn't do that because the unit was cooling properly. Should the A/C ice up and reduce the air flow on occasion; and, if so, then why has it not happened on previous trucks and cars I've owned? Am I just getting my usual "snow job" from tech's that don't read the TSBs?

 

[CCutshaw]

Make sure the condenser coil is clean. The AC will ice up if your not getting good air flow through it. Hope this helps.



Calvin

 

[DaveHess]

I had this happen to me once with my 2003. I was towing through the Smoky Mountains in a torrential downpour last summer. I turned the temperature control on the dash to add a little heat to the A/C and all of a sudden I had ice cold air again. Something iced up and thawed when I added heat but I did not stop to see what and it never repeated the incident again. I did not go back to the dealer because ours never wants to fix anything. So, you're not alone.

 

[formula]

hummm... ... I think if the condensor was clogged you wouldn't get good cooling at all and no ice buildup either because the heat won't get removed from the evaporator fast enough.



As far as things icing up, try running the blower on a higher speed to force more air over the evaporator, this may provide enough heat input to keep it from icing. Also, check the air intake to see if it's clogged with leaves or something.



Sean

 

[nps]

Check your refrigerant charge. When the charge is too low the coils and line will freeze up. It is not normal. Have the dealer recharge and check for leaks.

 

[Dieseldumb]

Just found out that the tech didn't check the lines with gages, but did the thermometer in the register check(what special training does that take?) and found 39 degrees on a 68 degree morning. I didn't say that the unit didn't work-just that it occasionally freezes up(which implies low refrigerant). When it's not iced up it cools fine. After me getting unfriendly, he has offered to check the lines but I've wasted my morning arguing with him and will have to bring it back in(or to another dealer). Why don't they realize the trouble we go to taking our vehicle to them(which gives them a job), and do the work right the first time(or do they even care)?

 

[dpatt67]

Dieseldumb: i had my truck in last week for that very problem and a couple of others. They had to order the parts to fix the problems(sticking door handle, clutch pedal binding, and the A/C) so i have to take it back in when they get the parts in. When i asked about the A/C, the service advisor said that the A/C tech knew exactly what it was and ordered the part. He didn't have the paper work in front of him so he couldn't tell me what part it was. As soon as it comes in i'll let you know what it is. Mine, only occasionally, would all at once start blowing warmer air in and i would keep cranking it up only to find more warm air, and of course when i looked at it the lines were all frozen. If you turned the A/C off for a minute the underhood heat would melt it and everything would be fine. Anyway, i'll post when i hear something.

 

[Carlsummers]

I'm sticking by my response in several other posts... fin temp sensor. My '03 did it, my '05 doesn't. I guess I'm really lucky... the dealership I go to listens if I tell them something is wrong, and has always provided my with the correct solutions, so I guess service depts are really a crap shoot on getting a good one.

 

[Dieseldumb]

Dave,

Looking forward to your reply! I also bet that it's the fin temp sensor. Does anyone have the TSB? Mine is a 2004, but built in the fall of 03(might be some overlap).

 

[Big_H316]

My '03 would freeze up everytime i ran it. Had the coolant charged up to the correct level (lbs. if you will) and it has never froze up since.

 

[RottonRob]

Dpatt67,

Did you ever find out what was wrong with your air freezing up

 

[RMarkey]

Maybe I'm asking an obvious ? here, but are you guys remembering to take it off max every once in a while? If not, after a little while, especially in humid climates, it will all of a sudden freeze up. Pretty common in the midwest, it's just something that happens on most vehicles there.

 

[DPKetchum]

Was told STAR is aware. fin temp sensor and relocation of it. Mine frreezes up on any blower speed on fresh every 50 to 65 miles of hiway driving.

 

[Task125]

Was told STAR is aware. fin temp sensor and relocation of it. Mine frreezes up on any blower speed on fresh every 50 to 65 miles of hiway driving.

did that fix the problem?

 

[DPKetchum]

Haven't been anywhere far enough to find out.