Help with heater question

[mjfuller53]

This is a new one on me. Can anyone help? On my 2005 Altima, I discovered a leak with the main radiator hose (it had come loose) and lost some coolant, but not too much. The car didn't overheat, but when I stopped after driving for several miles I could smell the coolant burning on the engine parts. I tightened the leaking hose and refilled the radiator. It took about a quart or more. Prior to finding the leaking hose I noticed the heat and air system wasn't heating. After refilling the radiator it works while the car is moving, but loses its heat when stopped and idling. Why is that? What could be the problem now? BTW, it has about 90,000 miles. P.S. I would check the fuses, but I can't tell from the manual which one operates the heater!

[SniperJoe]

You may have air in the system after you lost/refilled the fluid. Just need to purge the air out.

[mjfuller53]

Thanks Sniper, but you're dealing with a non-car mechanic basic dummy here. I do just enough myself to be dangerous. So how do you purge the air out? Can I do that or should involve a professional?

[mrodrig2]

Purging is done by pushing out the air through the radiator cap, a coolant bleeder valve (which I'm sure there is one but don't know where it is) or both.

Let your car cool down all the way.Open up the radiator cap.Fill with coolant if necessary.Loosen the bleeder valve.Start your car.Put heat on full blast.Let the car idle to get up to temperature twice (as indicated by your fan kicking on) or until no more air bubbles out.Shut off car.Close bleeder valve.Top off coolant.Close radiator cap.Let engine cool down.Recheck coolant level, check for leaks.

That's pretty much how to do it on my Civic, I'm guessing the procedure is the same or very similar for the Altima.

[mjfuller53]

Thanks Mrodrig2. Now can you or anyone else tell me where the coolant bleeder valve is located on the Altima? Or is there an online service manual somewhere? Thanks for any info.

[CoupeVQ35CVT]

A quick note, the heater works via blowing air over a heat exchanger of sorts (if you want to picture a mini radiator inside the car) that uses the same hot coolant from the engine. If I understand correctly, almost every car uses this method to heat the heater core, and passing air over it as opposed to heating the air electrically like a home appliance as I used to think (which would put additional load on the alternator and therefore engine).