temperature control system using peltier modules

I am fairly new to simulink but i have had some little experience and for a final year project i need to design a temperature control system using simulink. This design should be able to do the following

• Accept inputs from a user(prefered temperature)
• peltier module should either heat or cool depending on desired temperature
• a fan should help in the circulation of the hot or cold air from the surface of the peltier modul

my progress so far is that i have figured out how the fan is connected and how the peltier is also connected but i do not know how to integrate the two systems to function as have described in a controlled chamber