Poor AC Performance 2019 3500HO

[Sixpac2]

Hi All,
Looking for information.
My truck is a 6 month old 2109 3500HO dually dual zone.
Purchased in the winter so did not use the AC.
Now that its hotter the AC performance is very poor for a new truck.
Can barely get 55 degrees out of the vents with fan on Hi and Temp to LO.
No sync and both on LO.
Played with recirculation on but so annoying and loud.
Helps a little but not much.
My Elcamino blows much colder and is 30 years old never touched.

My old truck 05 3500 never blew cold but I knew I had blend door problems.
So I was excited to get a new truck and new AC.

As is standard today I started searching the internet.
Found all kinds of complaints on poor AC in the new 2018-2019 1500's and the 2019 HD units.
They seem to have mostly the same HVAC
The common dealer fix is it works within specs when taken in.

So my question is how is everyone else and is there any TSB, recalls or any ideas.
Blend door again or something else.
Why do these new trucks have such poor AC

Thanks for any ideas

Marv

 

[TFucili]

Welcome to Mopar HVAC. The problem is more pronounced on the dual zone climate control. There seem to be a few things going on. First there is constant flow through the heater core, and is apparently not contained well enough, so the AC is fighting the heater. Some guys have proven this out by bypassing the core, or installing a valve, and the temps drop noticibly. Then, either related to this, or something to do with the blend door(s), my driver's side center vent will blow about 15 degrees warmer than the center passenger vent. I keep a stick thermometer in my vent all the time, and have watched it over and over. Next, there is a theory by someone with HVAC experience that there is a sensor and/or programming issue. I know for sure if my wife takes it out of synch by upping the temp on her side a couple degrees, mine will sometimes start doing all sorts of wacky stuff, like suddenly blowing scalding hot air out my side for no reason. Some have found low refrigerant charge, but almost always get "working as designed" from the dealer. I haven't wasted my breath.

 

[Wiredawg]

My wife has a 19 Ram 1500 Laramie Longhorn 4x4 and it blows super cold. Haven't bothered to insert an HVAC thermometer... It has dual zone that we keep on 72. San Antonio TX has heat and humidity. Last week, it was 98'F when we took our Mobile Suites 5th wheel to get inspected pulling with 2017 Ram 5500 ... I ran the temp down to 65 to see how it did... froze us out. HVAC thermometer read 47'F.

I feel for folks having AC problems... great AC is the most important creature comfort in a vehicle, IMHO.

Good luck figuring yours out!

Cheers, Ron

 

[gsbrockman]

What is the ambient air temps when you’re experiencing 50*F vent temperatures?

 

[R.Taylor]

Need one of these to compensate.....

 

[KBrennan]

The AC does suck big time on the 2019s. Poor design I guess. I would like to know a good fix that won't void the warranty as well.

 

[Randomrunner12]

You could do what others have done and pull the dash to cut out the screens in the A/C and get more volume of airflow.

 

[KCJackson1]

Disappointing to read all this again. The AC in my 96 Ram was average at best, and the 05 has been an HVAC nightmare. Hard to believe FCA still hasn't figured this out. The Fords I owned prior to the 96 Ram had their issues, but HVAC was not one of them. Climate control should be a basic must-always-get-right system of any vehicle.

 

[Randomrunner12]

You would think and hope so. My wife's dodge journey has no issues with its quad zone AC ( front/ rear 2nd and 3rd row) blows hard and cold on all settings synced or not. Makes me want to pull the system from a junked journey and retro fit it to my 2012 lol.

 

[Tuesdak]

Disappointing to read all this again. The AC in my 96 Ram was average at best, and the 05 has been an HVAC nightmare. Hard to believe FCA still hasn't figured this out. The Fords I owned prior to the 96 Ram had their issues, but HVAC was not one of them. Climate control should be a basic must-always-get-right system of any vehicle.

A... HAHAHAHA! Maybe with the near 100 degrees in Detroit going on now the engineers and Bean Counters can finally sweat their **** off in their poor AC designs that have plagued pickups and SUV's (well everything running an obsolete FOT on the krap R134a gas) to the point that WORKING COLD AC is the #1 reason imports have kicked the Big 3 into insolvency.

Design a vehicle in a MI snowbank while ignoring the AZ proving grounds and this is what you get. The political pressure to use as little refrigerant as possible from the EPA doesn't help along with CAFE not wanting to kick a MPG sucking fan on or use a BIG enough MPG sucking compressor with related BIG condenser and MPG sucking airflow through a BIG grille...

The biggest DUH! I get is kicking the AC compressor on with defrost, no matter what, causing the water at 32 degrees to ice up and stay iced up longer than necessary on the windshield.

Experience an expensive replace everything "Black Death"? That term was invented from FORD AC system failures...

The usual performance improvements apply. Bypass the heater core, strap a electric fan on the condenser, check for bugs clogging the condenser, light off high idle in parking lots etc, evac and recharge the AC system just to be sure it's charged correctly.

Anything near 160 degrees, 300 psig, on the condenser is pushing the limits of the AC system bordering on overheating. You can measure with a cheap IR gun and this will answer the question of IF a electric fan will help. 45MPH+ should not require ANY fan.

 

[kthaxton]

The biggest DUH! I get is kicking the AC compressor on with defrost, no matter what, causing the water at 32 degrees to ice up and stay iced up longer than necessary on the windshield.

The AC dehumidifies the air, this helps with defrost. They've been doing it that way for decades because it works. I wouldn't call that a "Duh".

 

[MarkEagleUSA]

I thought engaging the AC compressor with defrost was to also keep seals, etc, from drying out?

 

[kthaxton]

I thought engaging the AC compressor with defrost was to also keep seals, etc, from drying out?

While cycling the compressor occasionally is beneficial.....AC is engaged with defrost to help dehumidify the air.

 

[Wiredawg]

While cycling the compressor occasionally is beneficial.....AC is engaged with defrost to help dehumidify the air.

Yep, when I was a poor Airman in the 70s and 80s, I bought basic trucks without A/C, auto, and carpet. Only thing I hated was Summertime storm, where I had to crank up the heat to dissipate the moisture and fogged windows. A/C works great to clear window fogging.

Cheers, Ron

 

[Tuesdak]

I see the fundamental problem now. Fogging is one thing. And frankly, it's not advertised as defog button or setting. 2018 Owner's Manual calls it Defrost! Alas it should be called defog and provide another true setting for Defrost.

I am talking about a cold windshield with water on it or building up frost quick ... and the engine isn't warmed up enough yet. So the AC running makes it worse aka RE-Frost rather than De-Frost. But no choice to run the AC or not it's just assumed and forced. Yes it can help at times, but, when it isn't helping it's a "DUH!" I would rather the AC button is a hard on/off without the "we are smarter than you" AC running in Defrost mode override.

I have been known to powebrake in the driveway to warm the engine up enough to "see" and blow the damn frost layer off. The AC running makes conditions where the windshield will frost back up when driving: again with a cold engine.

 

[gsbrockman]

The compressor only engages at temperatures of 32*F and above.

 

[Timd32]

To the OP, maybe its something with the dual zone, but my 18 Gasser, tradesman single zone works great, would not think the 6.7 would be a factor in this.

Would not think what you have is on point at 55 deg.

But try the fan in front of the truck if you are just sitting in the drive way trying this out.

Make an appointment for.sure to get that looked at.

 

[Ozymandias]

04.5 - fantastic Air-Con, even at Death Valley temperatures I've nothing to complain about.

Same with my 2012 Durango with Tri-Zone AC.

Same with the 2011 Compass my wife had.

Same my good old 1998 Grand Cherokee.

Nothing to complain about Chrysler/FCAs Air-Cons. Really not.

 

[JR]

To the OP, maybe its something with the dual zone, but my 18 Gasser, tradesman single zone works great, would not think the 6.7 would be a factor in this.

I rate the HVAC system on my 14 Tradesman a C+ at best. A/C is barely adequate as of late with heat index approaching triple digits. If I take it off of recirc or the highest fan setting I'm sweating within a few minutes.

Last summer I recharged the system from scratch thinking that was the problem with no change. The only thing left for me to do is add ball valves to both ends of the heater core. This helped my 98 a little.

And the fan speeds on the Tradesman are very poor. In single digit temps and below it's everything it can do to keep the windows clear on high. I have good heat just not enough CFM. My 20 year old VW pushes way more air in half the cabin space.

 

[Ozymandias]

You don't have by accident a clogged cabin air filter do you?