Introduction: ESP8266 Wifi Thermostat for Freezer

Picture of ESP8266 Wifi Thermostat for Freezer

The thermostat in my freezer said goodbye at the worst, with a lot of heat in July and an empty pocket after the summer break. So I started replacing, therm-mechanical element with an inexpensive ESP8266 system, which I can also monitor from anywhere (from home for now).

Step 1: Drawing the Scheme of the System

Picture of Drawing the  Scheme of the System

As you can see, the following list of materials is required:
1 dual power supply 5v and 3.3 volts dc.

1 Temperature sensor DS18b20 (Water proof is better with a couple of meters)

1 ESP8266-01

1 block of relay (I used a double because it is the one I had)

1 (4k7 ohm) resistor

Step 2: Assemble and Connect

Picture of Assemble and Connect

As was urgent, I did not bother too much in the aesthetics of the whole, so I soldered with tin, cables and thermoplastic, on a piece of uniprint plate.

Note: Very important !!, be careful to connect the ESP8266 to 3.3volt DC and the block of relays to 5 volt DC, if done backwards it is very possible to destroy the microcontroller.

Step 3: Program ESP8266 With Arduino IDE

Picture of Program ESP8266 With Arduino IDE

Using Arduino IDE and the appropriate libraries, the thermostat will easily be started, remember to connect the N / O normally open circuit of the relay to the old thermostat connections.

Important Note: To do this, remember to disconnect the main power from the refrigerator, to avoid damages by electric shocks.

Follow another better Instructable, to load the program via USB and serial port.
It is also possible to check the IP address of the thermostat. That IP address is where you can monitor temperature and the status of the relay through the wi-fi network., using http://ip_address/read

Comments

ronklo (author)2017-08-29

Hi, How do you set the temperature, or can this only monitor it?

braserito66 (author)ronklo2017-08-30

You can found setting temperature in .ino program, it is very simple. You select setting temperature before download.

It should be possible to program in a different way. Even make setting temperature as a variable you could change via server page, using commands via web server-client. Remember I´m using an ESP8266 ESP-01 with no GUI. Any way you could add code you can found in another Instructable, in order to adjust and visualize process and setting temperature using for example a I2C display.

ronklo (author)braserito662017-08-31

Thank you. I'm thinking to use this for my pool heater so I can monitor and set the termperature remotely.

diy_bloke (author)2017-08-19

Seems downloading of yr program keeps failing

braserito66 (author)diy_bloke2017-08-19

Hi, could you write, what kind of failure IDE report?

diy_bloke (author)braserito662017-08-19

It just reported as 'Faulty' in my download list. However just tried again (after a couple of restarts of my browser) and now it seems to work so the error was probably on my side. Sorry about that.

With that out of the way: nicely done. I have a DS18B20 in my Freezer and fridge, but that is just to monitor, doesnt regulate anything, but now I know it could

braserito66 (author)diy_bloke2017-08-19

Ok. Now I'm happy to know, it was helpful for somebody, please if you made it please mark "I made it" and add any images

Thanks

diy_bloke (author)braserito662017-08-20

currently just monitoring, bu if it comes to replacing my thermostat i will