A heat exchange system includes a shell having an interior with an inlet and an outlet wherein a first fluid circuit is defined from the inlet, through a heat exchange volume within the interior of the shell, to the outlet. A tubesheet is mounted within the shell dividing between the heat exchange volume and a plenum of a second fluid circuit within the interior of the shell. A set of tubes extends through the heat exchange volume, a respective interior passage of each tube being in fluid communication with the plenum through a respective opening though the tubesheet. The second fluid circuit includes the plenum and interior passages of the tubes. A spray nozzle is mounted in the plenum of the second fluid circuit with a spray outlet directed toward the tubesheet for cleaning the tubesheet with a submerged impingement jet issued from the spray nozzle.