I just changed my cooling fan with a 12in. aftermarket electric fan that I have hooked up to a switch. The original fan wasn't kicking on so when I was at a standstill or in traffic, the temp needle would rise. After taking the car out for a run after finishing up the temp needle just climb untill it was in the red...maybe 10min into driving. I wasn't even off my street yet. It wouldn't do that before, even with the original fan not working. ANY HELP PLEASE......

 

This may or may not help, but maybe your prior fan wasn't broke, i noticed when my CRX was running the fan wouldn't kick in until maybe ... 3-5 minutes in then it would stop, then start running again. apparently it runs when needed, are you sure you put the same voltage type of fan on there? sorry if i am not answering this in the right way it's hard for me to explain things.
i do know switch fans stay on all the time, but maybe you should get a fan that was exactly like the old one.

 

any coolant in the radiator?

 

did you put it on right there is 2 fans one is a pusher one is a puller.

 

x 2!