In this section you will learn about all the hardware devices that you will need to buy your own Smart Thermostat.
The basic components to build your Smart Thermostat are:
- An old Android 4.1+ device, that will act as the main controller. You can use an old smartphone of tablet. This device has to stay at your home and will be always on, because it will control your boiler and communicate with the cloud and the client app.
- At least one ESP32 mcu.
- With a DHT11 or DHT22 temperature/humidity sensor and a
- An one channel relay.
- Some protoboarding cables.
The above are the components needed for the minimum viable setup. You may add as many nodes as you want (for example, to register the temperatures in other rooms of your house). Buy you have to take in account that you can only have one relay per thermostat.
If you have doubts, don’t hesitate and ask in our forum, before buying anything.
And we assume that you have and Android device (smartphone or tablet) to install the client app and control the Smart Thermostat, and a internet (wifi) connection at home 🙂
1.- A one channel
You can use a low level triggered relay, or a high level triggered relay. The following is a low level triggered relay:
An the following is a high level triggered relay:
2.- Protoboarding cables
You will need male – male cables, male – female and female – female, like these:
3.- ESP32 board for a wireless sensor or wireless relay
You need at least one ESP32 board, in combination with a relay and a temperature sensor. Or you can split this unit in two, and have two separate ESP32, one with a relay, and one with a temperature sensor. Of course, you can add as many temperature nodes as you want.
4.- DHT11 and / or DHT22 Temperature Humidity sensor
For the wireless sensor, you will need one of these (connected with the ESP32). The DHT11 is the cheapest sensor, but the DHT22 is better, more precise and reliable. We strongly recommend the DHT22 sensor.
5.- Micro Usb cables
To power the Pi and the ESP32 boards, you will need micro usb cables. You can use cables that you have already, but if you not:
6.- 5V chargers
And to deploy your wireless sensor and the Pi across your home, you will need 5V chargers to power them. Something like that (or you can reuse old smarphone chargers):