First, I would drain and refill the system again. Chances are there is an air lock in the system! It is very easy to drain and slowly refill, just get the front of your car up and put a clean bucket under the rad, take the lid off the overflow bottle, open the stopcock at the bottom of the rad (you may have to remove the plastic undertray if present). Let the coolant drain fully into the bucket (~2 gallon capacity in the system), then close stopcock and very slowly add the fluid, let it trickle in to the bottle.

You should be able to reuse the fluid since it's new anyway (assuming they renewed it when they replaced the fan) otherwise get a new bottle for $20 at the dealer and mix 50/50 with distilled water.

As you add the fluid gently squeeze the large rad hoses to "burp" air out. Once the level is up to the middle of the overflow bottle, replace the bottle cap, lower the car and take it for a short drive, then you can top it up again - slowly.

Apparently it is common for people to add fluid too fast and introcude a large air bubble, the only way to get it out is to drain and refill the system.

I flushed and renewed my coolant a couple weeks ago and it was easier than changing oil (less messy too!) I used the Haynes manual as a guide and they stress this adding fluid slowly - so I did and had no problems.

Good luck!