Kirstystewart

Hi Please help! Yesterday I took my car on a test run to my job it was 40 miles there and we turned straight back, I went up a hill then down and the over heating error came on (my car doest show temperature bars) I pulled over and the fan was going crazy I turned off the car and called the rac as the car had plenty of coolant the rac couldn't find any problems restarted the car after 30 mins and the overheating error did not come back on, drove the car all the way back. as I have a new job I had to do the journey again today only to find the exact same spot it came up again as over heating just before the error came up the car fans were blowing colder air so I pulled over left the car off for 10 mins and then drove it home does anyone have any ideas? I have had my Citroen C3 for 6 years and changed the thermostat this year sorry if this doesn't make sense but if someone could help me please