armadillo

My heat/defrost controls do not work correctly on my 98 XJ and I'm afraid it was designed this way.
1) I can't get any heat unless the fan is on. Most vehicles allow the high pressure area around the cowling to force a little outside air through the heater and into the cab without fan assist. Is it normal for Cherokees not to work this way? I have to wear out the fan continuously even when I only need a tiny bit of heat. Thousands of hours of continuous operation can't be good for the fan.
2) Whenever I use the defroster, the AC kicks on and off. I can undrstand this might be useful if the inside of the cab was wet and there was condensation inside the winshield, but I'm in a cold, dry climate and there is never any need for it. I figured I could just disconnect the AC compressor wire every winter and solve the problem, but the cooling fan kicks on, too. I don't want or need a cooling fan on when I start the Jeep to melt the ice on the windshield and come back later.

Is this how they were designed to work or is something wrong? Anyone found any solutions to these problems of uneccessary wear and tear?

xjsnake

Yeah that's how they work. I think mine lets some heat out without the fan on but it's not much.

As for wear and tear, I really don't see that being a problem.

The cooling fan cycles on and off fairly quickly and won't affect warm up time all that much.

armadillo

Thanks for the reply. There are 3 components which are uneccessarily subject to extra wear; the radiator cooling fan, the AC compressor and the heat/AC fan. The first two, which are under the hood, would be subject to wear in the coldest mornings which might be as low as 10 below zero around here. The AC compressor can be unhooked every winter, but it wouldn't be a good idea to disconnect the cooling fan. I would like to disconnect the AC signal to it if there is a way.

Doobie97

Small amounts of air will flow into the cabin. Mostly not noticeable. The A/C turns on to remove moisture. Annoying when you live in a dry climate, but not unbearable. As for your auxillary cooling fan cycling on and off, install a switch next to the rear window wiper and rear defrost swtiches. This way you can control the on and off of the auxillary cooling fan.

I personally don't have any issues with Jeeps design, but to each their own.

armadillo

I was thinking of doing something like that. I think there are 3 things that control the auxillary cooling fan now; the AC, the defroster and a thermal switch that senses engine temperature. I would prefer to keep the latter operational year round and the AC control operational in the summer regardless if I forget and leave the switch off.