To begin, clean all the surfaces of the copper cooling block with 70%ethanol in the water cooling assembly. Wear gloves and apply a thin and even layer of around 0.4 grams of thermal paste to one surface of the copper water cooling block. Ensure the surface orientation will prevent the tubes from crossing or bending.
Similarly, clean the hot surface of the peltier using 70%ethanol and apply the thermal paste to the surface. Connect the peltier hot surface to the copper cooling block surface with thermal paste following the orientation of the wire. Apply pressure to secure it and clean the excess thermal paste.
Then make sure the 12 volt power supply and the tunable power supply are off. Connect the red wire of the peltier to the positive output and the black wire to the negative output of the tunable power supply using an alligator clip. After rechecking the electrical and water cooling assembly connections, switch on the 12 volt power supply and tunable power supply sequentially.
Gradually turn the tunable power supply to 12 volts so the current should be around six amperes with the suggested peltier. After two minutes, measure the temperature with an infrared thermometer without touching the cold surface, which should be colder than minus 35 degrees Celsius.
