Easy start for automatization with ESP8266

 Climate control project

Sensors in the project

  • Board temperature
  • Air temperature
  • Air humidity
  • Heater temperature

Devices in the project

  • Cooler of board
  • Heater
  • Fan or Air extraction
  • Humidifier
  • Fuse


The project is based on the board Wemos D1 mini with the ESP8266 chip. It's a board like Arduino, but more small and powerful with WiFi system inside. Project definitions:

  • SelfTemp - sensor for board temperature control.
  • AirHum, AirTemp - module for air temperature and humidity in the house.
  • HeatTemp - sensor to control the heater temperature.
  • SelfFan - operate with cooler of board.
  • AirHeat - operate with heater. 
  • AirFan - operate with fan. 
  • AirHumid - operate with humidifier. 
  • FuseHeat - operate with fuse.

Attention! This is a typical schema and can be changed as you decide. It's not necessary to use all components! 

Project component list
# Marking Amt Type Model Description
U1 1 pc Module WeMos D1 mini WiFi board with 4MB flash based on ESP-8266EX
BME2801 pcModuleBME280 I2CTemperature Humidity Pressure Sensor
DS18B202 pcSensorDS18B201-wire digital temperature sensor, TO-92
D1, D2, D3, D4, D55 pcDiode1N40071000V 1A General Purpose Rectifier Diode, DO-41
Q1, Q2, Q3, Q4, Q5 5 pc Transistor 2N3904 0.2A Ic, 40V Vce, Small Signal NPN Transistor, TO-92
R1 1 pc Resistor 4K7 Resistor 0.25W, THT, DIN 0207
R2, R3, R4, R5, R65 pcResistor1KResistor 0.25W, THT, DIN 0207
K1, K2, K3, K44 pcRelaySRD-05VDC-SL-C10A Relay SPDT SANYOU SRD Series Form C
J11 pcSocketMKDS 1,5/2-5.08
KF301-2P
Way Screw Terminal Block 17.5A 5.08mm
J11, J12, J15, J164 pcSocketMKDS 1,5/3-5.08
KF301-3P
Way Screw Terminal Block 17.5A 5.08mm
J81 pcSocketB2B-XH-A(LF)(SN)JST XH Series P2.5 mm
J3, J42 pcSocketB3B-XH-A(LF)(SN)JST XH Series P2.5 mm
J21 pcSocketB4B-XH-A(LF)(SN)JST XH Series P2.5 mm
optional?RelaySSR-40 DASolid silent relay
optional?Power supplyHLK-PM01AC-DC 220V to 5V 
optional?CoolerMX-3010Radial fan 30x30x10mm, 5В 150мА


Danger! The relay of the device operates with a high voltage circuit, be careful! 

Useful and smart! These PCB components are optional to use. For example, in one way you can use digital pins for your relay module, or in another way, you can put on board all components and make a complete product. The board has additional pins like 5V, 3.3V, GND for outside modules. 

The SelfTemp sensor may be placed right on board without sockets.

There is a high voltage zone on the PCB. It is necessary to solder well all wires from the relay.

You need to connect the fuse on the wire path before all other devices. A fuse can cut off the circuit and save the heater from overheating in case of a broken relay situation.

Board's box
Socket cover of the heater
Box for BME280
Fan adapter