Introduction: Making a Dual Pump Peltier Cooler Module.
Peltiers tend to be inefficient for heat removal. Their coefficient of performance is typically less than one. To get the cop higher, the Peltier needs to be undervolted to reduce the waste heat created internally. However the rate of heat removal will be reduced.
To overcome this drawback at a higher cop, several Peltiers can be installed in parallel and run at lower than rated voltage to have a greater than 1 cop rating. This means that for every 1 watt consumed, more than 1 watt of heat is transferred to the hot side of the Peltier. This is what we need to make an effective cooler.
To test each Peltier, I applied 1volt to each. Good Peltier modules pull 0.5amp at that test voltage.
Step 1: Heatsinks.
Using spare aluminum heatsinks lying around, I put these aside for the project.
Step 2: Cleaning.
Using paper towel and rubbing alcohol, I cleaned all surfaces of the Peltiers and heatsinks.
Step 3: Thermal Grease.
Using thermal grease left over from cpu installations, I put a thin layer of grease onto the required surfaces.
Step 4: Putting the Dual Pump Module Together.
Two plastic cable ties were sufficient to hold the heatsinks together and sandwich the 2 Peltiers.
Step 5: Prototype Testing.
Wiring the Peltiers in series and powering from 6v including the axial fan for the hot heatsink, I took some measurements. A delta T of 6C was achieved in less than 90 seconds. The power consumption is 6watts. This is quite good!
Each Peltier gets 3v for operation which significantly reduces the waste heat generated and therefore raises the cop.