Since the topic is heater, and the colder months are amongst us now. I am curious how the operation of the heater system works. I have a manual will look into a bit more, but wondering if anyone has direct knowledge of this.

My issue, when car is warming up, I notice it getting warmer of course in the heat. I start to drive around, drop daughter off at school, and then on my way to work, sometimes I have to wait a long time at the RR crossing because it is a two track crossing, there could be two trains going by or a train that is passing through that is actually slowing down across the crossing. I'll sit there with my brakes on for a long period. It is from my experience and training at school that power brakes operate off vacuum when is use.

I just remembered, it doesn't even require the brakes, a bit more down below.

Not to throw off topic, but my instructor said it would save people gas by giving plenty of space between vehicles so braking wouldn't be needed as much even for tapping, since it is taking vacuum.

Anyways, since that is the case, I think that when I am pressing the brakes, I feel the heat start to diminish. I brainstormed it a bit, I have concluded it is either a comfort thing that when idle helps with keeping the inside from not flaming up in heat? It'd be nice if Chrysler corp thought that nice of us wouldn't it.

I say that because I was waiting for my wife in the Wal-Mart parking lot for like 20 min. I had the heat on full blast (probably the defrost on too, can't remember) but I remember it blowing out the vents. With idle the heat just really ceased to exist, I had to rev the engine up to get some more heat flowing. So I guess a combination of two things, braking the heat slowly turns down, sitting idle the heat slowly turned down.

Other than that, everything works fine, maybe it could be the engine coolant was doing it's job and keeping the flow cool enough not to open the Tstat. When the engine is working that heat is like nuclear power as in another thread discussed. I think the operation is fine, just wondering of thoughts about this. I don't know what my Tstat range is, but I know that summer to winter, my temp gauge never goes above half, it sits comfortably below it.

 

this is just general info.

most temp guages are nothing more than fancy idiot lights. while they do provide more info than a light they norm only have 3-4 positions/ranges. cold, warming-up, norm, and look out. this prevents unneeded service checks for those who do not realize that like oil pressure, coolant temp NEVER stays the same when the engine is running around town. the t-stat is always opening and closing, adjusting for the heat load the enigine is producing. closing when the engine is at idle (outside temp is a big factor), and opening more under load.

if, like my '02, your heater core is tied into the cooling circut (after the coolant comes out of the t-stat), you will lose heat production when your engine cools off, like sitting in the parking lot for 20 min. of course if you live in the tropics you have another issue.

hitting the brakes should have nothing at all to do with heat production. the only thing that might be somewhat norm is a slower fan speed because of the brake lights drawing more of a load from the elect system. i'm thinking you have a bad vac hose someplace. i could be wrong here, but to my ear it sounds like the flaps on my ride are controlled by vac. if you are losing pressure through a hole, it could be slowly closing a flap to the heater core thereby cutting stopping airflow across it.

happy motoring

 

I agree to a bit that the vacuum might be an issue. I know if I leave the vents (have to check which position) to a certain position, I hear them electrically close when I turn off the car. Not like my old '88 E-150, that was an obvious closing when the vacuum was lost, spring loaded I am sure (never took it apart). Mine is all electrically controlled, the servo (assuming that is what is used) you can tell rotates through positions. Like if it is off, it will go through the defroster porting before it gets to straight vent porting. Does that make sense? So you know, when I turn off the engine, I hear that servo closing back up.

My wife's 05 Neon still uses levers and such from the control *****, but mine is all electrical, so that is why I was wondering what is causing the heat source to be variable, would that be an electrically controlled vent so when I do sit at the RR crossing for a period of time and the engine is relatively still cold but warming up, I feel the heat diminish because of the Tstat regulation.

See, this is new to me. I have never been in a situation waiting in the cold of the morning and winter, as I am now more. I just moved here this past summer, so waiting at RR crossing wasn't something of my everyday routine. It was start up, let it run a bit to warm up, then go to where I need to go. Just trying my resources as how this functions.

 

most cooling systems are tested in death valley, it gets kinda hot there. if like me, you have snow on the ground and temps are in the single digits, your t-stat WILL close with no load because your cooling system is so effecient, evan with the engine running.

 

Ok, well I am glad that someone else is thinking that too. Just logically that is what makes sense. I thought I'd throw that out there and well, see a yay or nay and I appreciate your time, I think I have a better educated guess about it now.