heat only luke warm when outside temp is below 30 deg.
have already replaced the blend doors. they were broken. they are working properly now. heater core good. new radiator. engine temp 210 deg f. if I pull it in my garage, maybe 50 deg or so heat will work very well. any ideas? thanks
Recheck the travel of the blend doors, make sure they make the full travel then check the recirc door, the recirc doors are also a high fail on these.
I have recirc door tie strapped closed. basically the position it would be in if recirc was turned off. have taken back off and rechecked circ doors.
So there is your problem, you are pulling in cold outside air instead of blending it with warmer cab air, it should be locked in the recirc position and if you have a problem with the windows fog turn on the A/C to defogger the windows.
thanks for your insight. I tried it the other way a couple months ago and the windows did fog. AC wasn't working at that time. I have fixed since. My thought process for closing the recirc so the windows didn't fog was that I never turn on recirc in my truck or my 04 grand Cherokee or any other vehicle unless hot day with AC on so I was assuming that all those recirc doors were in the same position that I tie strapped the '99 GC recirc in. Am I thinking correctly? Thanks for your thoughts on this matter.
On a normal system your thinking would be right but as this is an HVAC system the recirc system is suppose to blend both cab and outside air to aid in cooling and heating. I don't why they just couldn't leave things along the old cable drive worked just as good if not better.
Your explanation definitely makes a lot of sense. I guess I'm just confused why I don't have to use the recirc button on my other vehicles that are equipped with recirc. Do they move automatically to different positions when you don't have the button on? I really appreciate all the time you have taken to explain this to me. thanks,
If your other have HVAC system then yes they do.
My other cars do have the recirc button. This makes a lot of sense now. I always thought the door was full open or full closed. Never knew it actually opened some and mixed on its own. Your answers were great and really appreciated. What do you think if I were to drill a few 1/4" or so dia holes in the recirc door before I wire tie it to the fire wall side so that it will let a little fresh air in and maybe not fog as much? thanks
That would work if you live in a high humidity area it would help.
Thank you for all your help. I will let you know how it works out.
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