The operating principle of the botijo is as follows: the stored water is filtered through the pores of the clay and in contact with the outside dry environment (characteristic of Mediterranean climate), it evaporates, producing a cooling (2.219 kilojoules per gram of evaporated water).
O principio de funcionamento do canabarro é o seguinte: a auga almacenada fíltrase polos poros da arxila e en contacto co ambiente seco exterior (característica do clima mediterráneo) se evapora, producindo un arrefriado (2,219 kilojoules por gramo de auga evaporada).