Temperature effects and thermally induced noise in photodetectors are significant in the detection processes. Degradation of electrical and optical characteristics of the photodetectors in the increased temperature conditions is one of the most important limitation factors for their application. Since most of the electrical processes in semiconductor devices depend, in some extent, on the temperature, investigations at temperatures higher than room temperature may reveal possible changes in output characteristics of the device. From the technological point of view, thermally induced noise increase minimum signal that can be detected, which is specially important for the low energy and non ionizing radiation detectors, since the noise level presents the major performance limitation. In this paper these effects are studied through frequency noise level measurements and measurements of the main output characteristics of photovoltaic components.