No heat
- Thread starter Morks
- Start date
. I’d put my money on the controls.
FamilyFunWagon
TJ Enthusiast
The heater controls are moving g the doors. The lines going in and out are hot. I ran water through the core and it seems to flow well. So, I have no clue.
The only thing I can figure is I put something together wrong inside
The only thing I can figure is I put something together wrong inside
If air is coming out the vents, and the water lines going in and out of the heater core are hot, then it about has to be the blend door isn't opening. That is where I would start looking. If the actuator is moving, then the door may be broken off inside.
I'm not rocket scientist or anything but if I had no heat and a knob that needed pliers to turn...that would be step 1. You're talking about a part that is around $20 and takes 4 mins to change. Why would you even THINK about the heater core until you eliminated that? Makes zero sense.
The blend door actuator fully goes in either direction as compared to my buddies 03. And if I manually turn it I can hear the flapper, could it still be that door?
The point of the post still stands true. It's the cheapest and easiest item to change. Why would you chase this problem without starting with the one screaming in your face?
While it is stiff it still works, that is my only issue with changing something that does "work" would the dial being stiff but still changing to the vents no problem be an issue?
lol, I'll order the part and see how it goes. Hopefully, it can come in in a timely manner.
After chasing this same issue of little to no heat (noticeably worse as the outside temp dropped) This had began for me after replacing everything in my cooling system (minus the heater core) and flushing the heater core several times. I had a thought/theory. I realized that the OEM radiator I took out was actually an automatic trans radiator, so the cooling area is effectively larger, and obviously didn’t have bashed fins like the old one. So my theory was that the new radiator was cooling so well that it was able to keep my engine right at or below 195 per the thermostat. I just threw in a motorad non-fail safe 205F thermostat and now I have dern good heat…
Edit… my temp gauge was showing around what I would estimate to be 190-195 prior to the swap. Now it shows just a hair lower than 210.
Edit… my temp gauge was showing around what I would estimate to be 190-195 prior to the swap. Now it shows just a hair lower than 210.
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The dial that selects which vents the air comes out is not the control that operates the blend door. The one that operates the blend door is the one that selects between red and blue.
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And that dial works perfectly! Just the vent selector that switches say between defrost and feet is stiff, but will change no problem when I do it with pliers.
Then I agree with you. Even if it is stiff, that is not your heat problem.
You said earlier, "The blend door actuator fully goes in either direction as compared to my buddies 03. And if I manually turn it I can hear the flapper, could it still be that door?"
When you say manually turn it, are you removing the actuator and turning it by hand?
With the jeep running, the blower on, do you feel any temperature difference from the vents when you manually turn the flapper? If not, then the flapper isn't working correctly.
If you aren't familiar with how it works, this video is a pretty good summary of what is supposed to be going on. What's inside a heater core box? (Around 5:30 is where he talks about the heater core.) His is an older jeep, so it has a cable instead of an actuator to operate the blend door.
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There is a sdifference, before I said on the one speed setting it is warm enough to just barely defrost once the engine is fully warm. there is a difference but when I put it on a higher setting it is warm for 2 seconds then cool again.
Speed setting is just blower speed. That shouldn't change the temperature, just how fast the air is blowing. Speed setting doesn't change the blend door position (unless it is possibly broken and free flopping in the air current).
When you say manually turn it, are you removing the actuator and turning it by hand up under the dash near your feet at the blend door?
Exactly, and the only thing I can think of is a broken door on the inside however, when I manually turn it I do remove the actuator and it moves freely.
AG10
Member