Mega cab Weak a/c

[jwc9]

Recirc and driving. Also I decided to give it a shot of artic 134 to see what would happen. I put in about 7oz ( half a 14oz can) and the drivers side now gets down to 35 and passenger is 48. It now cools the cab very fast. I am a happy boy! Although it is still not right thaat the temp is higher on one side I can live with it. I wish someone or maybe I will pull the dash apart and try and see why it is like this. There has to be a door that is not funcioning right.

 

[DPKetchum]

Mine on RECIR does reasonably well but on fresh its 20 degrees differance. It can be 15 degrees diffrance,stop like at a redlight,start off and pass. side puts out a blast of hot air that can make pass side 30 degrees differance and then try to cool back down as you drive. Drivers side only changes a couple of degrees. If morning is in low 70s its hardly noticable but if 90 plus its very obvious to whomever is in pass seat.

 

[gtobey]

I can tell a difference like that in mine from recirc to fresh, I just have not measured the temps. I tried turning the mode knob all the way to defrost and back stopping at each setting for about a second or two, and with our 106 degree day here, it did seem to blow a bit more air out of the dash vents after it made it's way from bi-level to upper vents. It sounds like when the engine turns off that the system does not stay where it was, but vents inside close, etc. , cause when you turn on the key, you don't feel air coming out anywhere for a couple of seconds even though the fan is blowing until something inside the AC box moves...



I just think that we are suffering because of their poor design. I will have to find me someone with a hand held anemometer that can check the flow at my vents to establish the "baseline" before I take it back to see if they can remove the screen...

 

[gtobey]

UPDATE 8/27/07



I went to a different dealer with the truck, and they determined from a GPOP bulletin which states, "... if the manufacturing date was before 5/06" then the screen over the evaporator should be removed. Apparently, this may have been mentioned before, but the screen is to make more air go to the rear vents, and they have determined that it makes the front worse, so they have to take the dash off to get the screen out. My pressures in the AC system are excellent, and the temperature out of the middle vents gets down to 40 degrees on a 97 degree day, but the air flow is just not there. I have an appointment with this dealer to have them perform this procedure as talking with the mechanic, he has done lots of them. He said it should make a difference...



We'll find out and post the results...

 

[231jasonS]

Well we'll be waiting to see what a diff it makes.



I pulled mine apart and the fan when out of the housing blows very hard and seems to move a lot of air. It has to be choked down after the heater core. I pulled the cowling and found a big piece of silver tape covering the air intake on the passenger side forcing air to come from the drivers side. I guess that was an attempt to not get hot air in the system from the exhaust. I removed the foil tape and it made no detectable difference. I put it back.



Where is this screen I didnt have the box out of the truck but removed a lot of the dash and was unable tell where it was.

 

[DPKetchum]

Are you referring to the post of 8/06? Yes 06! If you got your ac to blow 19 degrees centigrade which is appx. 68 fahrenheit I apologize. If you're referring to that post in 8 of 06 and you meant 19 degrees fahrenheit its not possable. The unit will FREEZE up and everyone who read that post that knows anything about auto ac knows thats NOT possible I'm just the one who said so.

 

[Megadesertdiesel]

"but the screen is to make more air go to the rear vents, and they have determined that it makes the front worse, so they have to take the dash off to get the screen out. "





the above statement is what i was told by a Dodge mechanic friend. he said " who makes the truck payment and wants cooler air? if they remove the screen then it allows more air flow to the front vents, BUT you will get less flow in the rear vents. " i am going in next week to have this done. and will let everyone know what happens.

 

[gtobey]

Well we'll be waiting to see what a diff it makes.



I pulled mine apart and the fan when out of the housing blows very hard and seems to move a lot of air. It has to be choked down after the heater core. I pulled the cowling and found a big piece of silver tape covering the air intake on the passenger side forcing air to come from the drivers side. I guess that was an attempt to not get hot air in the system from the exhaust. I removed the foil tape and it made no detectable difference. I put it back.



Where is this screen I didnt have the box out of the truck but removed a lot of the dash and was unable tell where it was.

I am not sure exactly where it is, because I haven't seen it, but they told me that it was above the evaporator/heater core, and its purpose was to restrict some of the air to the front vents so that a bit more went to the rear. But I think too much of it ends up being directed somewhere else, or ends up just making a restriction in the system...



I will report more when I learn it...

 

[johnglaw]

I have an '07 megacab with less than 2000 miles on it. My a/c has quit twice already. It will blow cold air for maybe 5 minutes and then hot air for 20 minutes. It never has cooled as it should. Have to keep the fan on high all the time. I just today got it back from the shop where they said they added one pound of coolant and found a loose connection on the compressor. Tomorrow going on a 6000 mile trip and will find out how it really works.

 

[gtobey]

I hope it works good for you, johnglaw. I took mine in to the dealer the last Thursday before Labor Day weekend, and they told me that they didn't have time that day to get the screen out over the evaporator core that day, but to bring it back on Monday the 10th of Sept. I'll find out then if it makes any difference... .

 

[Megadesertdiesel]

well i got my truck back today from the dealer and WOW a big difference. now the front vents blow air and dont make a lot of noise. i had the door replaced and the screen removed.

 

[gtobey]

Picked up my truck last night from the dealer, Dominion Dodge, in Salem, VA. They performed the proceedure that folks have been mentioning here about replacing the recirculation door and removing the screen that is supposed to direct more air to the rear vents. I must say, if you have the low air flow to the front vents, go ahead and complain to the dealer so that they will perform this procedure. My receipt contained the numbers CSR# 39 and a number of 24652300 which may have been a part number. It really makes such a difference that when I was coming home last night from the dealer I was looking to slow the fan down (I thought I had it on the third setting), (86 degrees with 75% humidity) because I was actually getting cold, but it was already on the lowest speed!!! What a marked improvement!!!!



Now, when you turn the fan on the highest setting, you can tell the vents are putting out the most amount of air they can for their size. The velocity of the air is fantastic!!! I have 38 degree air coming out of the center vents with the fan on high and recirculate, so it should cool it down quite a bit better now!!!!



This dealer has done a lot of these repairs, and their diesel guy is certainly well trained and experienced because there are no rattles, and the dash looks like it did before the work was started. You can't tell anything has been done! My hat's off to him. Great job!



If anyone has any questions about this, feel free to PM me. I can only say that I highly recommend this repair from my experience with this problem. Everyone in this particular thread that recommended it apparently has experienced the same thing. This is a load off my mind because it will help keep the wife comfortable, and ultimately, if she's cool and happy, I will be happy. Because, everyone knows... "if momma ain't happy, then nobody's happy... "



Thanks for listenin' to my 2 cents worth...