CCKen

I'm retired. LOL

Cherokee

ok, so I took a good look around and tried different settings and here is what I found.

From what I can tell, I can see the recirculating air door right by the passenger side firewall kickpanel. When I turn the control to Max AC the vacuum controlled door opens up.

When I move the controls from hot to cold it correctly changes temperature decently quickly.

When I change from vent to heat (lower vents) it changes airflow alright.


So my conclusions are that maybe with the controls on "Heat" its just letting in air from somewhere and its so cold out that my fiance can feel it. When I have the temperature all the way hot and turn the controls to "Max AC" the cold air flow lessens significantly. So maybe my system works correctly? I just don't understand why when the control is on Heat it ends up being colder than when I have it on Max AC. Why wouldnt the recirculating air door close for the heat? I don't have enough refrigerant for my AC compressor to turn on even when I have the controls to all the way cold (no point recharging it right now). But is this not a good longterm solution to just stick it on Max AC for better heat?

CCKen

You need to verify that the recirc air door (MAX AC) is closing fully. If this doop=r is not fully closed it will allow outside air to enter the cabin. The Heat control **** moves the Blend Air Door, in the full Heat (red zone) air is driven accross the heat exchanger, and when in the full cold (blue zone) the heat exchanger is blocked off and air is forced though the AC Evaporator. The two vent positions, face/floor only positions the panel/floor door.

Read through this thread. He had a similar problem.

https://www.cherokeeforum.com/f2/hva...needed-165661/

Cherokee

ok great, yeah that makes sense.

I actually didnt really remove the dash at all to do this investigating so I'm probably looking at the wrong door opening and closing. When turned to max ac this door actually opens, but stays closed on all other settings. What is that door then? I actually started to take all the dash apart but it was just too much work for the free time I had so I never actually got the glove compartment off. seemed like a lot to undo to get it off though.

thanks for the replies, i know almost nothing when it comes to this hvac stuff

CCKen

You don't have to remove the dash like the other person did; he had other issues that required repositioning the vacuum tubing to the recirculation air door actuator.

You just need to access the recirculation air door and its actuator by removing the kick cover that covers it and see if the door is fully closed when a mode selection other than MAX AC (Recirculation) is selected. To do this you need to access the door, start the engine, place the mode selector in the MAX AC position then another position other than MAX AC. The door should open then close fully when not in the MAX AC position. There should be no air gap around the door. If the door remains ajar, it will allow outside air to leak into the cabin.

Refer to the pic below. MAX AC (Air Recirculation) is setting 11. This position moves the recirculation air door open to recirculate the cabin air through the HVAC unit, and when closed it allows outside air to move through the HVAC unit.

If you select position 8 (panel outlet) or 7 (floor out), these are the "Vent" positions. The recirculation air door should be closed in any of these positions. In these positions the Temperature Selector determines the temperature of the air coming out of the panel outlet or floor outlet.




Behind this Kick Cover is the Recirculation Air Door.



Recirculation Air Door and its actuator.

CCKen

Addendum to above post:

While examining the Recirculation Air Door, check to see if the actuator lever is properly hooked to the door and see if you can move the door by hand.

Test drive the vehcle with the kick cover removed and the mode selector in position 8 and the temp selector in full heat. While driving (with someone in the passenger seat) hot air should be coming out the panel outlet (above the radio) and no air coming out of the floor outlet on the passenger side). Have the person in the passenger seat hold their hand down near the floor outlet/recirculation air door area and see if cold air can be felt.

Cherokee

ok well judging by this I was looking at the correct door then. It moves freely and closes well when on any setting beside max ac.

problem is the air seems to be coming from behind the glove box not all the way down there. i've never noticed the air until this year bc i dont ride in the passenger seat often, so maybe this little bit is normal? just seems too cold to be ok.

thanks for all the diagrams, you've been quite inciteful

CCKen

The seal around the blower motor or the vent seal on top of the HVAC unit may be leaking.

CCKen

Cherokee,

Now that you're finished hijacking Burgy's thread perhaps you could ask him how he's made out with his problem.

Jerry Wagenhoffer

Most likely the problem is from the seal. Take it back under warranty repair.