Surface condenser efficiency can be improved by maintaining clean heat-transfer surfaces, sufficient cooling-water flow and a stable vacuum. Scale, silt and biological deposits inside the tubes create thermal resistance, so the tubes should be cleaned regularly by mechanical brushing, chemical cleaning or an online sponge-ball system where appropriate.

Cooling-water strainers, pumps, valves and water boxes should be inspected to ensure an even flow through all tubes. Low flow reduces heat transfer, while excessive velocity may cause erosion. Removing trapped air from the water boxes also helps prevent inactive tube areas.

Air leakage on the steam side must be minimized because non-condensable gases reduce the effective heat-transfer area and increase turbine backpressure. Expansion joints, flanges, instrument connections, valve stems and vacuum-system piping should be checked for leakage. Air ejectors or vacuum pumps must also operate correctly to remove non-condensable gases continuously.

Condenser performance can be further improved by maintaining proper condensate level in the hotwell, preventing excessive condensate subcooling and keeping tubes above the condensate level available for steam condensation. Cooling-water distribution, tube plugging and tube-material condition should be reviewed during outages. A high number of plugged tubes may justify retubing or tube-bundle replacement.

Operating data—including condenser pressure, cooling-water inlet and outlet temperatures, flow rate, terminal temperature difference, condensate temperature and dissolved oxygen—should be trended over time. A gradual increase in backpressure or terminal temperature difference often indicates fouling, air leakage or flow-distribution problems. For older units, improvements may include corrosion-resistant replacement tubes, upgraded air-removal equipment, divided water boxes or an optimized tube bundle.