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WTH is wrong with my A/C?

4K views 20 replies 17 participants last post by  goodriddance 
#1 ·
Never dealt with this before but the A/C blows cold out of the driver side vents and on the passenger side it is not cold. Hardly even cool.. They produce equal amounts of air, just different temps. Thanks guys.
 
#3 ·
Do you have dual zone control?
 
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#4 ·
I have the same problem it's the pass side blend door In mine at least. I would check charge first though being it is much easier. pass side blend door the dash needs to be removed
 
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#7 ·
Low freon or a blend door.
 
#9 ·
Cooler air on driver side than passenger is usually the first sign of a low refrigerant charge due to the design of the evaporator coil. Usually you can just top it off with a can of r134a and be good for a year or two; however if you find yourself constantly having to add then you have a leak somewhere and need to do some digging to find the root of the problem.
 
#11 ·
I'm is the complete opposite. I have cool air out the passenger side and warm air out driver side. I am thinking the blend door is messed up. How hard is it to change and what is the normal cost of it. Has anyone done one and is there a step by step instructions somewhere on here. I know that I have found all kinds of help on replacing things here. Thanks for any help everyone.
 
#12 ·
Mine is single zone and charging it fixed it. I also have bad dampers... I've had the Heater treater parts for two years! It's a lot easier to plug the heater core nipple in the head every summer than to pull the dash. Craig
 
#14 ·
I know my blend door is broken but I ended up charging my a/c and it is blowing cold out of both sides now. I need to fix the mode door for defroster.
 
#15 ·
From the Heater Treater web site: "Most auto makers constructed the core with refrigerant flowing from top to bottom on dual systems. With this setup (Dodge trucks) both sides would be the same and a lack of efficiency in the core would be equally spread across both sides. Chrysler moves the refrigerant from right to left, so if there is a temperature gradient across the core (due to a low refrigerant level), the passenger side is at the back of the core and will see less efficient AC (heat exchange). Charging the system may solve the problem and at least it should be checked."

In my case I connected a manifold gauge set and noticed both low and high side pressures were low. The driver's side was 20 degrees cooler than the passenger side. I serviced the system with 10oz of refrigerant (and a can of red dye) and I'm good to go. Fortunately, I all my doors are functioning properly!

Here are all the details from Heater Treater:

Dodge Ram 2002, 2003, 2004, 2005, 2006, 2007, 2008, blend door auto AC heat replacement part
 
#16 ·
Mine just started doing the same thing 2 days ago.... warm on passenger side only. Since it had been fine (39° @ the middle vent) I found it hard to believe I was low on freon. I was dreading having to change the blend door though, so I drug the gauges out and checked the freon. Sure enough, I was running 20lbs @ idle and it would drop to less than 10lbs when the fan kicked up.

Shot some freon in it, and it is back to freezing me out on both sides now. I found I have a slow leak at the A/C Accumulator by the firewall. It was quite a relief.... not a real expensive part, and a fairly easy fix.... no pulling the dash.

So if youre having this issue with warm/hot air on the passenger side, at least check your freon before you tear your dash apart. You may save yourself a lot of time, money, and hassle.
 
#17 · (Edited)
Mine just started doing the same thing 2 days ago.... warm on passenger side only. Since it had been fine (39° @ the middle vent) I found it hard to believe I was low on freon. I was dreading having to change the blend door though, so I drug the gauges out and checked the freon. Sure enough, I was running 20lbs @ idle and it would drop to less than 10lbs when the fan kicked up.

Shot some freon in it, and it is back to freezing me out on both sides now. I found I have a slow leak at the A/C Accumulator by the firewall. It was quite a relief.... not a real expensive part, and a fairly easy fix.... no pulling the dash.

So if you're having this issue with warm/hot air on the passenger side, at least check your freon before you tear your dash apart. You may save yourself a lot of time, money, and hassle.
Did you mean the low side pressure dropped to 10 PSI when the compressor started? Yea, that's a little low. I had leaks at both schrader valves, so I tightened them up. I haven't seen any red dye, so I think slow leaks at the schraders caused my problem.

Remember, Freon is a Dupont trademark name for automotive R12 refrigerant, so I hope you didn't put R12 in your system ... not that you can find or afford it.

For the rest of you out there with similar problems, I've attached a couple of great links. See page 188 of the first link to see what your gauge reading should be based on ambient air temperature and humidity.

Today's Technician: Automotive Heating & Air Conditioning - Mark Schnubel - Google Books

This link provides great information on automotive AC systems:

http://www.ariazone.com/manuals/Automotive Air Conditioning Training Manual.pdf
 
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