Temperature gauge going to maximum

I just bought a 2009 Aveo LS with 23,000 km on the counter 2 days ago and after driving for 10 minutes, the temperature gauge reads maximum. There was leakage when I bought it but after changing a couple of hoses, the leaking has stopped. This car was only used during the summer. Right now, everything looks fine. What could cause the overheating? If I turn on the heating system to maximum, the temperature gauge stays at mid point. I only paid 800 dollars Canadian for the car....knowing that I had to repair the leaking coolant.

If the guage stays at max, you might wanna check the thermostat. Usually when thermostat valve fails, it causes overheating issue. You might wanna check radiator if the coolant is foamy around the cap. Check it when the engine is cold. You might have to deep flush coolant radiator.