None of this is even remotely difficult. What are your problems ?
Why "but there are some errors, it didn't work what I have expected"
Help us help you.
1.) How accurate is your time requirement. (Use the site search for examples of other peoples problems)
2.) How did you measure temperature ? What precision of temp. reading do you need ? How often do you need to measure it ? What happens in your system if the sensor fails ? (Use the site search for examples of other peoples problems)
3.) How are the relays wired ? Ordinary relays are going to generate horrible switching noise without some care. Why not use ZVC triacs (see the thread lower down) (Use the site search for examples of other peoples problems)


Steve