A/C Performance

[Ram4Lou]

I just did a little test and pulled the cabin filter out, and ran the AC on recirculate. It was like the blower had 2 extra high speed settings. It actually is blowing like every other car I’ve driven.

are we sure it’s just for outside air?

I concur with your thought. My understanding is that the filter is directly before the evaporator coil. So all airflow goes through the filter to protect the coil, regardless of whether in recirc or fresh.

I’m not 100% sure on this Ram because I haven’t needed to change the filter yet. But on every other vehicle I’ve changed them on, the filter was always right before the evaporator coil. Would be silly not to protect the coil during recirc as well, since there is still dust and pollens that get into the cab every time the doors are opened.

Edit: I just went out and checked the truck, figured might be good to check the filter since I’m at ~22K miles. The filter was not too bad (see pic), but confirmed that the filter is directly upstream of the evaporator and blower motor. Blend door to switch between fresh and recirc is above the filter. So all air goes through filter, regardless of blend door position.

 

[Ram4Lou]

My 2021 Laramie has good AC. But...I wonder.

My '03 Honda Pilot has a coolant shutoff valve, electric, slaved to the climate control. If I want heat, it's open and fills the heater core with hot coolant. With the AC on, that valve closes, and keeps the hot coolant out of my air box.

I would LOVE to retrofit a similar valve onto my truck. I'd want it slaved in to the climate control. Barring that, I could wire it into a spare switch on my center console I guess.

Hmmm....

This looks to be a pretty good option.

2-Port, Electro-Thermal Linear Actuator with Heater Control Valve 12V Normally Closed 5/8" P/N 740975

Electro-Thermal Actuator opens/closes the valve which controls the coolant flow through a vehicle heater core, providing heat to the passenger compartment. Duty Cycle: When heat is called for, unit is energized. Orientation mandatory, wires down +- 90 degrees.

www.thermotion.com

 

[theblet]

I concur with your thought. My understanding is that the filter is directly before the evaporator coil. So all airflow goes through the filter to protect the coil, regardless of whether in recirc or fresh.

I’m not 100% sure on this Ram because I haven’t needed to change the filter yet. But on every other vehicle I’ve changed them on, the filter was always right before the evaporator coil. Would be silly not to protect the coil during recirc as well, since there is still dust and pollens that get into the cab every time the doors are opened.

Edit: I just went out and checked the truck, figured might be good to check the filter since I’m at ~22K miles. The filter was not too bad (see pic), but confirmed that the filter is directly upstream of the evaporator and blower motor. Blend door to switch between fresh and recirc is above the filter. So all air goes through filter, regardless of blend door position.

View attachment 163398

Thank you. I em pretty sure the filter is right above the blower motor. Like you said, all air is passed through it.

I’d like to find a less restrictive filter to use. The one I have now is a basic charcoal one, not hepa or anything. The only other one i see is maybe the K&N one. It looks like you can see daylight through it so that may be a better option. I wish I could get one that was just a screen.

 

[turkeybird56]

like i said, still gonna be hot as hell

U think, lmao. I have tinted windows, and use the Artic Breeze Brella (just for convenience) and also keeps windows cracked a lil (1 front/1 rear), which all helps dissipate heat but with 100 F plus everyday, hot.

RAM fan does HAVE 7 speeds but never been known to Blow you out of the truck.

ADDED: When RAM did the redesign and started using Blend Doors, instead of a HCV, so allowing hot coolant to flow through the core 100% of the time, U know U R fighting physics. U could clamp the Heater core inlet hose from the water pump, or put some type either manual/electric activated switch in that line. There are threads on this. I actually do have a manual valve and associated parts, just not put in as my truck sits 99% of the time.

 

[theblet]

U think, lmao. I have tinted windows, and use the Artic Breeze Brella (just for convenience) and also keeps windows cracked a lil (1 front/1 rear), which all helps dissipate heat but with 100 F plus everyday, hot.

RAM fan does HAVE 7 speeds but never been known to Blow you out of the truck.

ADDED: When RAM did the redesign and started using Blend Doors, instead of a HCV, so allowing hot coolant to flow through the core 100% of the time, U know U R fighting physics. U could clamp the Heater core inlet hose from the water pump, or put some type either manual/electric activated switch in that line. There are threads on this. I actually do have a manual valve and associated parts, just not put in as my truck sits 99% of the time.

Oh yea. I already have a valve on the inlet, there’s about 2 years. I also had the AC TSB done so it’s not really needed anymore. Just trying to get it to blow!

 

[HSKR R/T]

U think, lmao. I have tinted windows, and use the Artic Breeze Brella (just for convenience) and also keeps windows cracked a lil (1 front/1 rear), which all helps dissipate heat but with 100 F plus everyday, hot.

RAM fan does HAVE 7 speeds but never been known to Blow you out of the truck.

ADDED: When RAM did the redesign and started using Blend Doors, instead of a HCV, so allowing hot coolant to flow through the core 100% of the time, U know U R fighting physics. U could clamp the Heater core inlet hose from the water pump, or put some type either manual/electric activated switch in that line. There are threads on this. I actually do have a manual valve and associated parts, just not put in as my truck sits 99% of the time.

Most car manufacturers went away from heater control valves in the 80s and switched to blend doors with coolant running through heater core 100% of the time. It's not just Dodge/Ram doing it. The valves were more prone for failing.

 

[theblet]

I ordered the k&n. It should be here Tuesday

 

[Ram4Lou]

Most car manufacturers went away from heater control valves in the 80s and switched to blend doors with coolant running through heater core 100% of the time. It's not just Dodge/Ram doing it. The valves were more prone for failing.

This is true. Problem is just like someone here already mentioned, you’re fighting physics. Even though the blend door isolates the airflow from the heater core, the heater core is still radiating heat to the plenum and airflow ducting. A HCV or “the hack” keeps the core from heating up at all. Also much easier to replace a faulty HCV than having to repair faulty and leaking blend doors and actuators. Most HCV were easily accessed in the engine compartment near the firewall. Blend door components commonly require major surgery under the dash and sometimes require complete dash removal. I prefer the old HCV systems.

 

[seansmd]

I ordered the k&n. It should be here Tuesday

Link to the k&n?

You said it's less restrictive?

 

[theblet]

Link to the k&n?

You said it's less restrictive?

They said that it has 25% more airflow. I’ve yet to find out until it gets here

K&N Cabin Air Filter: Premium, Washable, Clean Airflow to your Cabin Air Filter Replacement: Designed for Select 2019-2021 RAM (1500, 2500, 3500) Vehicle Models, VF2065 https://a.co/d/2tFqnyZ

 

[seansmd]

They said that it has 25% more airflow. I’ve yet to find out until it gets here

K&N Cabin Air Filter: Premium, Washable, Clean Airflow to your Cabin Air Filter Replacement: Designed for Select 2019-2021 RAM (1500, 2500, 3500) Vehicle Models, VF2065 https://a.co/d/2tFqnyZ

Ok just ordered one too.

Just ran a test removed the factory filter(left it empty), drove for 20 minutes MAX AC, lowest it measured with an infrared thermometer was low 50f out of any of the vents. It was blowing much stronger, but this seems much higher than i expected.

Is there a factory range that service will within spec?

2023 limited, Phoenix 111 degrees out during test.

 

[theblet]

Ok just ordered one too.

Just ran a test removed the factory filter(left it empty), drove for 20 minutes MAX AC, lowest it measured with an infrared thermometer was low 50f out of any of the vents. It was blowing much stronger, but this seems much higher than i expected.

Is there a factory range that service will within spec?

2023 limited, Phoenix 111 degrees out during test.

I did the same test. Blows like a bat out of hell without the filter. I think it’s undersized. Some say 40 to 45 degrees on the center vents, but I’ve never seen under 50 since its 100 degrees and 80% humidity. I’d say you’re prob good.

 

[HSKR R/T]

You'd be lucky to get output more than 40 degrees below outside air temp. And actually on MAX A/C with highest blower setting it won't blow as cold as a lower blower speed

 

[Lpsouth1978]

After doing the A/C hack on my truck, I am getting 44-46F from drivers vent with 110+ temps Drove the truck 9 hours yesterday, from southern Phoenix to Big Lake and back. It worked perfectly and kept us cool the entire time. I wish I had done it earlier.

I changed to the K&N cabin air filter a long time ago, though I can't say I noticed a major change in blower performance.

 

[theblet]

You'd be lucky to get output more than 40 degrees below outside air temp. And actually on MAX A/C with highest blower setting it won't blow as cold as a lower blower speed

I measured mine at blower speed 5, so it could read colder on low.

 

[Ram4Lou]

After doing the A/C hack on my truck, I am getting 44-46F from drivers vent with 110+ temps Drove the truck 9 hours yesterday, from southern Phoenix to Big Lake and back. It worked perfectly and kept us cool the entire time. I wish I had done it earlier.

I changed to the K&N cabin air filter a long time ago, though I can't say I noticed a major change in blower performance.

^^^this. I’m getting more than 50 degree temp drop as well with hack. I sometimes see temps dip into high 30’s, but right now low 40’s.

 

[Dyeelitt]

My air conditioning started to lose performance. I received a UConnect update, as we were driving, the AC got very warm, stopped blowing and then started cooling but didn’t seem to be as cool as before nor the volume of air as strong. I also noticed when I set the AC to AUTO, the fan speed highest setting is 5 or 6. I can change it to 7 but then the AUTO is disabled. I took it to the dealer in Reno and they said there is nothing wrong. I have another appointment for SoCal when I get back this week. The recirculating door also doesn’t always actuate. I pulled the cabin filter and blew it out, it was a bit dirty and the truck is 9 months old and 10,000 miles. I ordered a new Bosch filter which is supposed to arrive today and I’ll replace it for our drive back to SoCal. The temperature out of the center vents was around 50 degrees in recirculating mode. The cabin still takes an extremely long time to cool down.

 

[HSKR R/T]

My air conditioning started to lose performance. I received a UConnect update, as we were driving, the AC got very warm, stopped blowing and then started cooling but didn’t seem to be as cool as before nor the volume of air as strong. I also noticed when I set the AC to AUTO, the fan speed highest setting is 5 or 6. I can change it to 7 but then the AUTO is disabled. I took it to the dealer in Reno and they said there is nothing wrong. I have another appointment for SoCal when I get back this week. The recirculating door also doesn’t always actuate. I pulled the cabin filter and blew it out, it was a bit dirty and the truck is 9 months old and 10,000 miles. I ordered a new Bosch filter which is supposed to arrive today and I’ll replace it for our drive back to SoCal. The temperature out of the center vents was around 50 degrees in recirculating mode. The cabin still takes an extremely long time to cool down.

50 degree vent temp is good. And the dealer will tell you it's working properly. Auto only blows full speed when initially starting. if you have the sunroof set it to vent until cabin stats to cool down. If no sunroof crack the passenger side window u til cabin starts to cool down. This will vent out the hot air and help A/C.

 

[6of36]

My air conditioning started to lose performance. I received a UConnect update, as we were driving, the AC got very warm, stopped blowing and then started cooling but didn’t seem to be as cool as before nor the volume of air as strong. I also noticed when I set the AC to AUTO, the fan speed highest setting is 5 or 6. I can change it to 7 but then the AUTO is disabled. I took it to the dealer in Reno and they said there is nothing wrong. I have another appointment for SoCal when I get back this week. The recirculating door also doesn’t always actuate. I pulled the cabin filter and blew it out, it was a bit dirty and the truck is 9 months old and 10,000 miles. I ordered a new Bosch filter which is supposed to arrive today and I’ll replace it for our drive back to SoCal. The temperature out of the center vents was around 50 degrees in recirculating mode. The cabin still takes an extremely long time to cool down.

Dirty filters can make a huge difference for air conditioning. car or house. Any time you set fan speed, you are overriding auto, and going manual. Every car I have ever owned with auto temp did that. It will still maintain set temperature, as long as you set mode for heat or a/c manually.

 

[llando88]

Just wanted to post and say how glad I am to find this info, and appreciate all the posts made by everyone here. It's great info.

The A/C on my '21 Ram 1500 has been struggling lately to keep up with the Florida heat. I put a thermometer on the center vent and it would not go below 52F (ambient 86F.) Which I thought was a bit high compared to my previous car.

I went to my local Ram dealer Monday to talk to them. The Service Writer told me they would not look at the truck unless it was blowing 75F or above. Uh, ok. So I left. My guess is the dealership didn't want to bother with the truck (they told me they "could not look at it today" and that I'd have to leave it.) I also believe I'd be looking at paying a diagnostic, because it sure sounded like they just did not want to deal with it, since it is probably a well-known issue.

I then did some research and stumbled onto this thread. Wow! I had no idea these trucks had such an ongoing issue with tepid A/C performance, but now I understand a lot more.

Looking at what I could do to improve this, I realized I had installed a Bosch 6090C HEPA cabin air filter back in May. Based on input here and elsewhere, this is probably cutting down my airflow, so I am going to remove that and install a K&N VF2065. As soon as I decide how it fits (there's no "flow" arrow, and there is this weird "curve" shaped to one side) I'll put it in the truck. I'll also try that "exercise the blend door" trick, mentioned up thread. I will also look into the hose hack, that sounds genius.

Otherwise I'm pretty happy with the truck; we bought it to tow a mid-size travel trailer, which it does well. We sold the trailer earlier this year, but I'm still happy driving it, and don't have any immediate plans to sell it, since it's paid for and all.