Sponsored

Rear AC vent airflow?

Lightsped

Well-Known Member
First Name
David
Joined
Dec 5, 2018
Threads
44
Messages
170
Reaction score
139
Location
Kennesaw/Acworth, Georgia
Vehicle(s)
2021 Willys, 2017 Tacoma Off Road, Honda S2000.
Occupation
Technology Research
Should the rear AC vents be putting out as much air as the front vents? When have the AC or heat on there is barely any air coming out of them. Have tried with AC in the various airflow modes (3rd knob on the right) on the controls.
Sponsored

 

Xcoaste

Well-Known Member
First Name
Ben
Joined
Oct 27, 2020
Threads
3
Messages
557
Reaction score
907
Location
PA
Vehicle(s)
2021 JLUR - Past - '13 JKU, '97 TJ, '93 YJ
You wont get as much air in the rear as in the front. I have to turn the fan speed up pretty high to feel it come out of the rear.
 

Retrograde

Banned
Banned
Banned
First Name
Michael
Joined
May 3, 2021
Threads
6
Messages
576
Reaction score
2,205
Location
God's Country, Idaho
Vehicle(s)
2020 JLSS, 1995 Chevy K2500
Occupation
Arms Dealer
Yeah... they don't do much. Their sole purpose is to sell Jeeps to families...

Me: "Look Honey, it has air conditioning for the children."
The wife: "Squeeeeeee!"
 

Heimkehr

Well-Known Member
First Name
James
Joined
Sep 3, 2020
Threads
31
Messages
7,034
Reaction score
13,959
Location
Pennsylvania
Vehicle(s)
2021 JLU 2.0T
The HVAC tubing run to the rear seats, via the center console,* would need to be properly molded in an ever-decreasing circumference in order to provide increased air flow. IOW, it would need to mimic the ductwork leading from the furnace to the rest of one's house.

Having seen what said tubing looks like under a partially disassembled center console, it's evident that it's too wide leading up to and at the exit point to compress (and thus increase) the flow of conditioned air sufficiently to get anywhere close to what exits from the dashboard vents. With this in mind, I'm content with the air flow that the upper rear vents do manage to provide.

*Remember that there are other mouths to feed, also, in the form of floor vents under the front seats.
 
OP
OP
Lightsped

Lightsped

Well-Known Member
First Name
David
Joined
Dec 5, 2018
Threads
44
Messages
170
Reaction score
139
Location
Kennesaw/Acworth, Georgia
Vehicle(s)
2021 Willys, 2017 Tacoma Off Road, Honda S2000.
Occupation
Technology Research
Never realized there were vents under the front seats? Are they putting out more air than the portion behind the console?
 

Sponsored

XJfanatic

Well-Known Member
First Name
Brian
Joined
Mar 14, 2021
Threads
33
Messages
891
Reaction score
1,652
Location
Indianapolis
Vehicle(s)
2020 JLU, 2020 JT, 1990 Mustang
Build Thread
Link
Under the front seats is for the heat/floor position up front.

mine put out pretty decent air for console a/c but nothing like a dedicated blower in other vehicles.
 

Headbarcode

Well-Known Member
First Name
Mike
Joined
Aug 16, 2018
Threads
26
Messages
7,782
Reaction score
17,829
Location
LI, New York
Vehicle(s)
2019 JLUR Stingray 2.0 turbo
Vehicle Showcase
1
It's simply the result of the conditioned air following the path of least resistance.

For a well balanced system, 2 things are required. Velocity and volume. First is decreasing the size of the duct work to maintain air velocity. Second is adjustable butterfly valves at each split in the duct work. Choking down the airflow in the legs closest to the supply will ensure that enough volume is farther from the supply. I'm HVAC-R certified but never brought the knowledge out into the field. Nothing against that industry. Just simply got a much better offer to run a different business.
 

The Fixer

Well-Known Member
First Name
Steve
Joined
Aug 7, 2019
Threads
22
Messages
1,091
Reaction score
1,186
Location
North Jersey
Vehicle(s)
2018 Mojito! JLS, 2018 Firecracker JLUSS
Build Thread
Link
Occupation
Teacher
I believe the rears work best with the switch set to dash vent only, not split between the dash and floor. My kids would let me know if they were too hot or too cold LOL.
 

Heimkehr

Well-Known Member
First Name
James
Joined
Sep 3, 2020
Threads
31
Messages
7,034
Reaction score
13,959
Location
Pennsylvania
Vehicle(s)
2021 JLU 2.0T
I believe the rears work best with the switch set to dash vent only, not split between the dash and floor.
Yep. That's been true for every vehicle I've owned with rear vents, including the JLU.


Just tell those in coach that air is only for those in 1st class. 😀
I'm going to use that one. :)
 
 



Top