Why is it that my car heat isnt working but my cars not overheating?

Have you used a diagnostic tool to measure the temperature of the engine coolant while the engine is supposed to be at operating temperature? Have you purged any leftover air pockets from the cooling system after replacing the thermostat? If the engine's temperature is over 200 degrees or so, you should have heat. If you still don't, direct your attention to the inside of the vehicle. The climate control system will need to have troubleshooting performed with it, including the blend door actuators for the temperature. www.repairpal.com/repair-shops