About 60 mm in length by 60 mm in width is the typical upper size limit for Peltier modules.

One side of the Peltier module contracts as it cools and the other side expands as it heats. This stresses the elements and solder joints. Since thermal expansion occurs on an inch per inch basis, the larger the cooler gets, the greater the stress becomes on the elements around the perimeter of the cooler.

In cases where the required heat pumping capacity exceeds that which could be provided by one Peltier module, additional Peltier modules can be used side-by-side. In special cases, Thermonamic will manufacture Peltier modules up to 80mm × 80mm.