Asphaltene precipitation and its subsequent deposition is a growing problem for the oil and gas industry. Not only does it hinder the output of oilfields, but it also causes significant issues in downstream refining. Blending incompatible oils and operations at high surface temperatures are some of the key causes of the instability of asphaltenes, which may lead to fouling and reduction in performance for refinery equipment, such as heat exchangers. In this work, a systematic investigation of crude oil properties and asphaltene behavior at high temperatures and pressures was done for the first time to understand the occurrence and the magnitude of asphaltene-induced fouling in heat exchangers. The physico-chemical characterization of the oil samples used in this study included the application of a novel methodology to separate the crude oil into asphaltene and multiple maltene fractions, with known properties such as molecular weights and densities. Asphaltene polydispersity, onsets of asphaltene precipitation and the amount of precipitated asphaltenes were also investigated, as well as the rheological behavior of the crude oils of interest. A novel experimental apparatus that can operate in batch and continuous flow modes was built and operated to investigate the behavior of crude oil blends at high temperatures and pressures. In batch mode, the setup was used to investigate the effect of temperature on asphaltene stability and precipitation tendency. The extent of fouling at high temperatures was further explored using the configuration in a continuous mode of operation. According to evidence obtained in this work, asphaltene solubility decreases with increasing temperature, which leads to the formation of asphaltene deposits on the wall of the heat exchanger tubes. This mechanism, which might seem counterintuitive, is different from the asphaltene behavior reported in upstream conditions. This study provides a solid foundation and valuable laboratory data to facilitate the development of computer models to predict the occurrence and the magnitude of asphaltene-induced fouling, and for the development of best practices to mitigate this challenging problem commonly found in refineries worldwide.