Chevrolet Repair: Overheating, 2000 chevy cavalier, dexcool coolant

Question
Hello..I own a 2000 Chevy Cavalier that has about 63K miles on it. Lately the temp is constantly one bar over the normal midway point on the temp gauge. It's been that way for a while, but lately it is going further over than that (especially when I put the heat on). What could be causing this? Should I get the radiator flushed? It has the 90K mile guaranteed red Dexcool coolant in there, so I thought it'd be fine now. What should I look for?
Thanks,
Neal

Answer
Hi Neal,
Just a little over shouldn't cause any concern, but some things to check are the fan belt condition.
The radiator fins to see if they are getting obstructed with dirt and bugs, or if the fins are getting bent over, restricting air flow.

And if you can see down inside the radiator tank and see the ends of the tubes, see if they are getting obstructed by mineral deposits.

Electric fan at the radiator? Make sure it is working.

Van