This prototype thermocycler controls the temperature of a set of tubes, rapidly heating and cooling through a specified sequence of temperatures. We aim to have similar capabilities to the OpenPCR machine.


  • ceramic thermoelectric cooler
  • large heat sink with fans
  • computer power supply (with at least 25A on a single 12V rail)
  • aluminum thermocycler block
  • aluminum plate between thermoelectric cooler and heat sink
  • thermal compound
  • 25A 12V motor controller (this works)
  • Arduino Uno board
  • Grove sensor shield
  • thermocouple and thermocouple amplifier
  • relay for turning on and off the fans
  • sensor wires


When running the thermocycler, we wrap the block in insulation (removed here for clarity). We also have a heated lid using a small thermoelectric device.


We control the thermocycler using a lesson in our online lesson platform. The controller executes a sequence of multi-step cycles. It uses a PID control algorithm to run the thermoelectric device. The fan is turned on whenever the target temperature is less than 90 degrees C.

Assembly instructions

Instructions will be provided when we have finished prototyping. Contact if you are interested in more details or beta-testing this project.