I tried to "burp" trapped air from my radiator and here's what happened. Took the rad cap of, turned the heat on and ran the car until the cooling fans came on, coolant got sucked down into the radiator. Then i turned the heat off. The coolant did not go anywhere in fact it started to spill out of the radiator. The only time it went down is when I had the heat on in the car. Is this normal? Shouldn't the therm open and allow coolant to flow thus the level in the radiator should go down and not spill out?

02 maxima. How many temp sensors do I have and where are they

I have a 2002 Maxima GLE. I replaced my radiator with an aftermarket radiator. Now I noticed that the cooling fans come on after a couple of minuets of driving. They come on even when the engine is running cool. We are having 30 degree weather but they still come on and won't shut off automatically. Normally after a long drive they come on and then will cut off after the engine temp is cooled down, but now they come on and stay on. Is this a temp sensor thing, or a fuse, relay.