The thermal load demands of a refrigeration system for storing yellow fever
(attenuated) and poliomyelitis 1,2 and 3 (attenuated) vaccines were evaluated, following the
Rede de Frios Manual for installation at a state level. The bases for the construction of the
mathematical models are in the mass conservation and energy balance equations. Control
volume analyzes are in accordance with the properties of working fluids such as enthalpy,
entropy, pressure, temperature and thermal exchanges. In addition, the best process efficiency
was analyzed in comparison with the coefficient of performance of each particular refrigerant
fluid in the refrigeration cycle and the monthly cost of electricity relating the price of the
cylinder containing the fluid, with the work of the compressor and the hours cold room
operation. Special software is used in order to optimize the organization of information and
understanding of results. In view of the data presented, it was observed that the R-134a fluid
tended to be the most efficient for the parameters of this thermodynamic cycle, since it has the
capacity to carry out the refrigeration process with the lowest compressor effort in relation to
other refrigerants. In addition, the cost (R$) of R-134a was the lowest in the cycle, since its
COP is higher, while R-404a was the second best evaluated and R-507a was the least viable
for the process.
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