The demand for cooling and dehumidification of indoor air is growing at a high rate worldwide. Producing cooled air by making use of solar power may seem paradoxical at first sight. However there exist thermal processes to produce coldness, in which water is cooled or air-conditioning is driven directly by a heat input from solar system. The R&D effort to develop solar cooling technologies has increased significantly in the last twenty years. This thesis project is concerned with a new patented small scale solar cooling system, the Thermo Chemical Accumulator (TCA), a technology produced by the Swedish company ClimateWell AB and is available commercially. The work was done both at the Solar Energy Research Centre (SERC) in Borlänge, and at the ClimateWell AB headquarters in Stockholm. In this project, measurements, parameter identification, modelling and parametric study were done in order to develop the Trnsys model of the TCA controller. Measurements established the foundation of the work in this project. It aimed to provide accurate and reliable test data of the performance of the machine that cover the whole range of operating conditions of the machine in reality through a set of well planned and carefully executed experiments. Moreover, two tests were performed to measure the coefficient of performance (COP) of the machine. The previous controller component in Trnsys (Type 214) controls the machine operation relying on the concentration of salt in the machine barrels without taking the operation temperatures into consideration. Obviously this has major drawbacks on the performance of the machine. The new developed controller (Type 216) bases its operation on the temperatures of the machine. A brief parametric study was performed both to ensure that the new developed controller is working properly and to investigate the effect of some operating conditions on the performance of the machine. Results obtained from simulations using the new controller model showed good agreement with measured data. The parametric studies showed that the heat sink temperature has a significant influence on the COP of the machine and that an improvement of the insulation of the machine components could improve the COP of the machine.