MATERIALS
See makeprojects.com/v/30 for recommended
suppliers and other sourcing information.
Plywood or medium-density fiberboard (MDF),
6"× 4"×¼" thick
Machine screws, #4-40, ¾" ( 12) with matching washers
and nuts
For each HVAC control wire controlled (heating,
cooling, fan):
Relay, 5V DC switching voltage, SPDT
Diode, 1N4002
Transistor, 2N3904
Resistor, 1.2kΩ
Eric Merrill
Arduino Ethernet microcontroller Maker Shed item
#MKSP9, makershed.com. Or pair an Arduino Uno
(#MKSP11) with an Arduino Ethernet Shield (#MKSP7).
Temperature/humidity sensor, Sensirion SH T11
Real-time clock (RTC) module for DS1307 real-time
clock chip
I/O expander chip, 16-bit with serial interface,
MCP23017-E/SP
LCD display screen, 16× 2, RGB backlight
Potentiometer, 10kΩ usually comes with LCD screen,
for contrast adjustment
ScrewShield Arduino prototyping shield Maker Shed
MKAD24
Pushbutton switches, momentary ( 2)
Power over Ethernet (PoE) cable set
Transformer, 9V DC aka wall wart
CAT5 cable long enough to reach from thermostat to
Ethernet and 9V DC power sources
Protoboard or perf board, about 2"× 3"
Resistor, 10kΩ
Wire, 20–22 gauge, insulated, stranded various colors
DIP socket, 28-pin
Screw terminals, 2-pin ( 7)
Project box, at least 6"× 4"× 2" or deeper if you use the
Ethernet Shield
TOOLS
Soldering iron and solder
Razor saw or other saw for cutting protoboard
Vise
Drill and drill bits
High-speed rotary tool with cutting wheel e.g., Dremel
Hobby knife or small file
Screwdriver, slotted, small
FTDI programmer for programming the Arduino
Computer with internet connection
PHP/MySQL server (optional) for remote web control.
The project will work without it.
Project code: Arduino sketch Make_Thermostat
and web page make_remote.php Download at
makeprojects.com/v/30.
55 Follow us @make
