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Air conditioning Hack

People have been clamping off and bypassing heater core hoses forever! If you don’t need heat , it’s a non issue. The bypass that feeds the heater core is tiny compared to the larger ports in the pump that cycle between the engine and radiator. Only hazard to clamping is if you were to damage the hose itself from being clamped. I went with the valve for more flexibility over a clamp.You folks are way overthinking this.
 
You might think differently if you had all the issues with the A/C that others have had.
Radiator or Heater hoses are not designed to be clamped. With the coolant temp typically at 215-220 degrees, the combination of them beign clamped & creating excess pressure could cause them to fail prematurely,leaving you stranded.
If I was going to go that route, I'd install a temperature/pressure rated ball valve.
 
Bypassing the heater core is not unheard of. And is what I suggested in my post. The clamping of the hose is what I questioned. It may never be become an issue, I personally would not take that chance.
 
The heater core circuit is a very low pressure, relatively low flow system. The water pump is really for pushing coolant around the engine, and into the radiator. The heater core circuit being plugged would have minimal impact on the rest of the cooling system. However, like mentioned above, the hoses aren't really designed to withstand any sort of external clamping, and it could easily accelerate the degradation of the rubber after multiple heat cycles.

But anyway, the first best thing to do is keep taking the truck into the service department and logging complaints of under performing A/C systems. The next best fix if an owner is going to take the matter into their own hands is to use proper hose fittings and either get a shutoff valve or create a bypass for the coolant going to the heater core.
 
I'd just like to thank KcRay for helping everyone and for posting items and information when we needed it most. I went through every single post within this thread and what this guy came up with is just amazing. My truck is a 2019 Limited with the pano roof. I live in Arizona and in San Diego. When I'm in Arizona the AC can keep up but it's not cold like it should be. I purchased a temp gauge for the vent and came up with the exact temps as pretty much everyone else.

About 50* coming out of the center driver vent and 43* coming out of the passenger center vent. I noticed that when I'm in my garage (open) with the engine cold, but 110* outside, the air coming out of the driver center vent blows 43* and because the heater core has not gotten hot yet, this is the same test as if you clamp or block off the hose. There is no doubt KcRay honed in on the exact problem with these trucks. The AC system for these trucks seems to work great, but it's how the system is performing...that's the problem.

the problem isn't that the AC system isn't any good and it is weak. In other words, the main problem was found and it's not a big deal, it will be completely solved in a short amount of time and the truck will be as good as we knew it was.

Anyway, thank you so much KcRay!!! And also like to thank the other guys that popped on at times to help with others asking questions and thanks for also posting photos, links, etc.

You are the man, KcRay. THANK YOU!!!! I'm off to the parts store to do an "AC HACK"
MQQSE
 
I'd just like to thank KcRay for helping everyone and for posting items and information when we needed it most. I went through every single post within this thread and what this guy came up with is just amazing. My truck is a 2019 Limited with the pano roof. I live in Arizona and in San Diego. When I'm in Arizona the AC can keep up but it's not cold like it should be. I purchased a temp gauge for the vent and came up with the exact temps as pretty much everyone else.

About 50* coming out of the center driver vent and 43* coming out of the passenger center vent. I noticed that when I'm in my garage (open) with the engine cold, but 110* outside, the air coming out of the driver center vent blows 43* and because the heater core has not gotten hot yet, this is the same test as if you clamp or block off the hose. There is no doubt KcRay honed in on the exact problem with these trucks. The AC system for these trucks seems to work great, but it's how the system is performing...that's the problem.

the problem isn't that the AC system isn't any good and it is weak. In other words, the main problem was found and it's not a big deal, it will be completely solved in a short amount of time and the truck will be as good as we knew it was.

Anyway, thank you so much KcRay!!! And also like to thank the other guys that popped on at times to help with others asking questions and thanks for also posting photos, links, etc.

You are the man, KcRay. THANK YOU!!!! I'm off to the parts store to do an "AC HACK"
MQQSE
Thanks for the shout out
I'd just like to thank KcRay for helping everyone and for posting items and information when we needed it most. I went through every single post within this thread and what this guy came up with is just amazing. My truck is a 2019 Limited with the pano roof. I live in Arizona and in San Diego. When I'm in Arizona the AC can keep up but it's not cold like it should be. I purchased a temp gauge for the vent and came up with the exact temps as pretty much everyone else.

About 50* coming out of the center driver vent and 43* coming out of the passenger center vent. I noticed that when I'm in my garage (open) with the engine cold, but 110* outside, the air coming out of the driver center vent blows 43* and because the heater core has not gotten hot yet, this is the same test as if you clamp or block off the hose. There is no doubt KcRay honed in on the exact problem with these trucks. The AC system for these trucks seems to work great, but it's how the system is performing...that's the problem.

the problem isn't that the AC system isn't any good and it is weak. In other words, the main problem was found and it's not a big deal, it will be completely solved in a short amount of time and the truck will be as good as we knew it was.

Anyway, thank you so much KcRay!!! And also like to thank the other guys that popped on at times to help with others asking questions and thanks for also posting photos, links, etc.

You are the man, KcRay. THANK YOU!!!! I'm off to the parts store to do an "AC HACK"
MQQSE
Thank you for the "shout out" glad we have a forum like this to help each other out.
 
the problem isn't that the AC system isn't any good and it is weak. In other words, the main problem was found and it's not a big deal, it will be completely solved in a short amount of time and the truck will be as good as we knew it was.
MQQSE

What makes you certain this will be solved? Are you optimistic that FCA is going to do something?
 
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What makes you certain this will be solved? Are you optimistic that FCA is going to do something?
It will probably get fixed, on the 2020 truck :rolleyes: Actually if you think about it, that would be FCA admitting there is a problem, which could be beneficial to '19 owners in the end. Only time will tell.
 
What makes you certain this will be solved? Are you optimistic that FCA is going to do something?

Absolutely nothing, I don’t think FCA will do anything about it for our trucks. I’m sure FCA looks at the AC temp much like the MPG, our MPG is less than desirable but it is what it is - nothing is broke. Our AC performance absolutely sucks but it’s not broke (in their eyes) so it is what it is. Pick a clamp or valve and get some solace knowing you CAN have cold AC....
 
Absolutely nothing, I don’t think FCA will do anything about it for our trucks. I’m sure FCA looks at the AC temp much like the MPG, our MPG is less than desirable but it is what it is - nothing is broke. Our AC performance absolutely sucks but it’s not broke (in their eyes) so it is what it is. Pick a clamp or valve and get some solace knowing you CAN have cold AC....

I am in total agreement with you and will be shocked if they resolve it. I hate to sound negative because I really wish they would take this issue head on and communicate to us. For those that say their dealer says they haven't received complaints, we have examples of dealers who have received numerous complaints. You put the valve on or clamp and it completely makes the truck a A/C rockstar!
 
That’s how I look at it, if they pony up and actually provide us with a fix I’ll be happy and impressed, however a valve that I can close when it’s hot here in the summer and then open for the winter works fine for me. I’m actually used to doing this on some of of the fire engines I’ve driven for years.
 
Can anyone provide better pictures to do this to a 3.6L?
 
That’s how I look at it, if they pony up and actually provide us with a fix I’ll be happy and impressed, however a valve that I can close when it’s hot here in the summer and then open for the winter works fine for me. I’m actually used to doing this on some of of the fire engines I’ve driven for years.


Current RAM buyers could give the vehicle very bad reviews to family, friends, and acquaintances, it is IMPERATIVE that Chrysler
remedy this huge issue.
 
Current RAM buyers could give the vehicle very bad reviews to family, friends, and acquaintances, it is IMPERATIVE that Chrysler
remedy this huge issue.
I have been up the chain with this and basically FCA says there is no design issue and 55F vent temp is spec at 90 ambient temps. Odd are if you are not getting that cool then you have a leak.
 
Not sure about logic where clamping the water fixes a/c performance for an a/c leak.
 
Not sure about logic where clamping the water fixes a/c performance for an a/c leak.

Then you don't know how a vehicle air conditioner works. Let me explain.

Inside your dashboard, you have a large air box that all the ductwork connects to. This houses the blower, the air filter, and various servo actuated doors to direct the air to different vents, the recirc door etc.

This box is made of plastic, and also holds two small "radiators" - the heater core, and the A/C evaporator, which are generally separated by some sort of partition down the middle of the air box.

The blend door is responsible for temperature. This door moves back and forth to direct air over either the heater core, or AC evaporator - that's how you get variable temperatures out of the vents. Unlike a home AC which is either in heat or cool mode, the blend door sweeps back and forth and in theory can give you 100% heat, 100% cold, or anywhere in between.

The heater core in these trucks always has hot coolant running through it. So the heater core is always at the same temp as your radiator.

Based on the system performance, current theory is that something is wrong with the airbox design or the blend door operation, which is causing air to blow over the heater core EVEN WHEN THE SYSTEM IS IN FULL COOLING MODE. Many members have reported that clamping off their heater core lines causes the air temps to drop 8-12 degrees which is a significant amount, and supports this theory.

This is why it is a "hack" as obviously the system was designed to have both the heater core and AC Evaporator in use. Regardless of what the problem is, people who have clamped off the heater core are reporting acceptable temperatures.
 
The heater core circuit is a very low pressure, relatively low flow system. The water pump is really for pushing coolant around the engine, and into the radiator. The heater core circuit being plugged would have minimal impact on the rest of the cooling system. However, like mentioned above, the hoses aren't really designed to withstand any sort of external clamping, and it could easily accelerate the degradation of the rubber after multiple heat cycles.

For the sake of argument, then why are hose clamps used at hose ends all over the truck? Those hose ends are getting just as heated (maybe more so) and going through as many multiple cycles but you never see a radiator hose, heater hose, etc. end degrade or deteriorate any worse than the rest of the hose. Not trying to be funny but how does the hose know where it's being clamped?
 
For the sake of argument, then why are hose clamps used at hose ends all over the truck? Those hose ends are getting just as heated (maybe more so) and going through as many multiple cycles but you never see a radiator hose, heater hose, etc. end degrade or deteriorate any worse than the rest of the hose. Not trying to be funny but how does the hose know where it's being clamped?

You are confused, hose clamps attach a hose to a fitting so it won’t fall off. The hack involves a clamp in the middle of the hose pinching off flow. I personally didn’t do the clamp, I installed a valve I can open and close. You need to back to the beginnng of this thread and look at the pictures s of a valve and clamp in regard to this problem.
 
For the sake of argument, then why are hose clamps used at hose ends all over the truck? Those hose ends are getting just as heated (maybe more so) and going through as many multiple cycles but you never see a radiator hose, heater hose, etc. end degrade or deteriorate any worse than the rest of the hose. Not trying to be funny but how does the hose know where it's being clamped?
It’s the difference between clamping without deformation to secure the hose at an attachment point vs clamping mid-hose to partially pinch/crush ithe hose and ntentionally restrict flow.
 
It’s the difference between clamping without deformation to secure the hose at an attachment point vs clamping mid-hose to partially pinch/crush the hose and intentionally restrict flow.

I see what you're saying now.... I'd agree that pinching down a designed flow line in the center or somewhere along the line other than the ends may not be the best in the long run (but it would probably take many years for an issue to show up). If it were me, I wouldn't totally clamp it down, just clamp halfway or so to allow some flow to get through yet still get some benefit from it. Fortunately, my A/C is working well so I don't need to bother with it at this point.
 

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