Temperature sensor

good day I'm here because I need your help I want to make a project to be able to control a refrigerator, to control to what temperature to maintain the freezing part and of conservation and as well its respective defrosting, well realize this small sketch that only serves me to feel the temperature there, I hope you have understood me, any query do it in the post

good day I'm here because I need your help I want to make a project to be able to control a refrigerator, to control to what temperature to maintain the freezing part and of conservation and as well its respective defrosting, well realize this small sketch that only serves me to feel the temperature there, I hope you have understood me, any query do it in the post

PD: my sketch was done with a thermistor, but I wanted the project to be done with a temperature sensor ds18b20, and activate the engine through relays, the operation of a refrigerator is as follows: cool for 6 hours and half an hour of thawing.

Hi,
DS19B20 Info Here:
http://arduino-info.wikispaces.com/Brick-Temperature-DS18B20

Relay Info HERE:
http://arduino-info.wikispaces.com/ArduinoPower