a/c issues....

[rolloffman504]

Ok guys I have a head scratcher and hopefully someone can point me in the right direction. I have a 2015 1500 crew 3.6, after driving for a 1hr or 2 the volume of air decreases out the vent and the fan is very loud which sounds like I have the recirculation on but I don’t. Thinking I have a broken recircultion door I pulled the upper and lower glove boxes so I could see better. Now what I noticed is if I have the fan on 6 and not on max a/c seams to work ok, but then out of the blue I watch the recir door open a little bit without the button being pressed. And now the crazy part, as soon as I put the fan on high the recirc dorm opens completely ???? again without the button being pressed and the recirc light is not on. Is there a way to “ recalibrate “ the system?? Beyond unplugging the recirc control I am not sure what to do and this still does not explain why the airflow decreases after driving for a while. Oh and I have manual controls , thank you for any inputs anyone might have and sorry for the looooong post lol.

 

[gfh77665]

If a system is able to recalibrate, I would disconnect the positive cable from the battery, and let the truck sit 10 minutes without power. Reconnect the battery and the systems will reboot.

 

[crash68]

Before I did the single zone Auto Climate control mod my '15 would close the recirc door when it was hot and I turn the fan to 7 with the AC on. It would sometimes close the recirc door if the cab was really hot/humid.
If you have the 8.4 radio, you might want to consider doing the Auto Climate control mod, probably the best mod I did.

 

[south7west]

Before I did the single zone Auto Climate control mod my '15 would close the recirc door when it was hot and I turn the fan to 7 with the AC on. It would sometimes close the recirc door if the cab was really hot/humid.
If you have the 8.4 radio, you might want to consider doing the Auto Climate control mod, probably the best mod I did.

Is there a thread for that mod? You got me curious lol

 

[crash68]

Is there a thread for that mod? You got me curious lol

With the 1500 you'll order the wiring harnesses for the temperature and humidity sensors from M² Mods
You order the sensors from AllMoparParts.com
You'll use AlfaOBD to enable the Dual climate control first, once the display shows both temp sliders you change it to single zone.
You don't need the bezel with the Auto button, the soft button on the screen works. There is also a completely optional sun sensor: 68230114AB
When I did mine, I replaced the factory harness to the mirror/humidity sensor but it's not needed and a bunch more work, the one from M2 is a lot easier.

https://www.ramforum.com/threads/ho...to-a-manual-temperature-control-truck.103456/

 

[rolloffman504]

Unfortunately I only have the 5 inch radio....( for now ) haha

 

[rolloffman504]

I could have sworn I seen a post a while back in the electronics area regarding recalibration, it was in a radio upgrade thread ??? may be it was just something to do with the radio lol as it was quite some time ago, or it could just be old age.....

 

[Hemi395]

I could have sworn I seen a post a while back in the electronics area regarding recalibration, it was in a radio upgrade thread ??? may be it was just something to do with the radio lol as it was quite some time ago, or it could just be old age.....

If you have Alfaobd you can perform a HVAC recalibration which runs all the actuators to their full sweep.

Are you hearing any clicking behind the dash? If not then I doubt you have a broken actuator or recirc door.

But I've noticed in the summer when it's really humid out the recirc door will open and close on its own to maintain a certain humidity in the cabin as per the humidity sensor.

 

[rolloffman504]

If you have Alfaobd you can perform a HVAC recalibration which runs all the actuators to their full sweep.

Are you hearing any clicking behind the dash? If not then I doubt you have a broken actuator or recirc door.

But I've noticed in the summer when it's really humid out the recirc door will open and close on its own to maintain a certain humidity in the cabin as per the humidity sensor.

Even with the manual a/c. ( I don’t have duel zone or single zone and the 5 inch radio), I ask because I never really noticed before maybe I just was not paying attention lol, thanks for the reply....

 

[rolloffman504]

Another reason is the recirc door will open when I put the fan on the highest setting, I played around with it for almost a hr today and could duplicate it every time and it was maybe 17 degrees today and low humidity ??....

 

[OCDTech]

Thought i read somewhere it may do this normally depending on the humidity.

 

[rolloffman504]

After a little research, humidity sensors are “standard “ in all Rams which explains the recirculation door movement. Now I just need to figure out my lack of airflow after driving for a while with the a/c on. I am thinking maybe the evap is either freezing up ( even though the pressures are fine) or the evap is dirty. Is there a way to clean/flush the evap to clean it ?

 

[Hemi395]

After a little research, humidity sensors are “standard “ in all Rams which explains the recirculation door movement. Now I just need to figure out my lack of airflow after driving for a while with the a/c on. I am thinking maybe the evap is either freezing up ( even though the pressures are fine) or the evap is dirty. Is there a way to clean/flush the evap to clean it ?

It may be freezing up. Easy way to tell if it is freezing up is to turn the AC button off and crank the fan up. If it slowly starts blowing more and more it's freezing up. Mine will do that sometimes if it's really humid out. My work van will as well.

Cleaning it is not easy unfortunately, it requires removing the dash...

 

[rolloffman504]

Thanks, I will give that a go to see if that’s the issue. What about back flushing through the drain hole for the a/c with some water? or would that possibly damage something ?? Just a idea lol. Thank you for all the responses, I really appreciate them......Love this forum !!!

 

[south7west]

Thanks, I will give that a go to see if that’s the issue. What about back flushing through the drain hole for the a/c with some water? or would that possibly damage something ?? Just a idea lol. Thank you for all the responses, I really appreciate them......Love this forum !!!

There's a product called LubeGuard Kool-It which does exactly what you want. You just spray it up the AC drainoff hose where all the condensation leaves the vehicle, wait a few minutes, and thats it. Pretty sure O'Reilly's carrys it. It cleans out the evap core and the heater core with a foaming solvent.

 

[rolloffman504]

Awesome TY south7west, I will see if they carry something similar up here in Canada

 

[south7west]

Awesome TY south7west, I will see if they carry something similar up here in Canada

No problem. It's not a bad idea to get some compressed air and spray some up after all the foam has run down and done its thing too. Good luck!

 

[rolloffman504]

UPDATE: I had a buddy of mine who works in a garage check it for me and I was down just a bit on freon causing the evap to freeze up. He topped it up for me and all is well again, nice and cold thanks for all the input !