Most of the semi-empirical "threshold fouling" models for crude oil fouling in shell-and-tube exchangers have been developed and validated using data collected at what may be considered to be "point" or localized conditions. In practice, both velocity and wall temperature can vary significantly within a heat exchanger, leading to difficulty in applying the models in exchanger design and extracting fouling information from exchanger performance monitoring. A partial simulation model is presented here, incorporating a linear temperature distribution. This short-cut model is compared with a more detailed simulation in order to establish its reliability. Pressure drop using a smooth layer model is also considered. The short-cut approach is employed in a data reconciliation study of an operating crude preheat train, which indicates that the original threshold fouling model of Ebert and Panchal gives a better description of the observed fouling behavior.