The principle of technological registration of biological objects fast freezing combined method is considered. The combined method provides adjustable tap of heat according to program freezing principle. Fast-freezing device with the output of 100, 250, 500 and 800 kg/h is the main part of combined cooling system. Thus the device is a system of modules in each of which it is possible to provide conditions, necessary for technological process, of tap of heat for realization of fast freezing process independently. The main technological idea of combined cooling system is to use full gaseous nitrogen refrigeration potential in the first module when the temperature of –30 deg С is maintained in the second module. The power and economic estimation of the combined cooling system working conditions is carried out. The results of the thermoeconomic model application show that it is economically unreasonable to low air temperature below –70 deg С in the first module and below –30 deg С in the second one.