Theoretical and experimental studies of heat exchange processes in the thermoelectric block of a refrigeration unit designed for ship freezers and provision chambers have been carried out. In the original design of the block, which includes 8 thermoelectric modules S-199-14-11, thermosyphons, a liquid heat exchanger with counter coolant flows and vacuuming volume were used to accommodate thermoelectric modules, which allowed minimizing heat losses and increasing cooling efficiency. Using a mathematical model, the performance characteristics and modes of operation of the refrigeration unit under different conditions and layout options are calculated. An experimental model of a thermoelectric unit was created and tested, the values of cooling power in various operating modes were determined.