An apparatus, system, and method for a gas turbine engine may include a sectioned heat exchanger. A heat exchanger may include an inlet manifold configured to receive a working fluid. A plurality of circuits including at least first and second circuits configured to transfer heat with respect to the working fluid. Each of the circuits may have a circuit inlet valve, a circuit heat exchange channel, and a circuit outlet valve. The heat exchanger may further include an outlet manifold configured to pass the working fluid to an outlet. The heat exchanger may include a first sensor configured to measure of first parameter of the first circuit and a second sensor configured to measure a second parameter of at least one of the outlet and the second circuit. A controller may be configured to selectively isolate at least one of the plurality of circuits based on a pressure difference between the first and second parameters.