Turbines equipped with surface-condensing plants offer better facilities for accurate steam-consumption calculations than those plants in which the condensed exhaust steam and the circulating water come into actual contact, it being necessary with this type simply to pump the condensed steam into a weighing or measuring tank.

In a surface condenser, inspection of the pumps delivering condensed steam to the measuring tanks or hot-well; inspection of piping between the condenser and the pump, and also between the pump and measuring tanks. If these pumps are of the centrifugal type it is essential to insure, for the purposes of a steam-consumption test, as much regularity of delivery as possible.

It is unusual, in those cases where a simple turbine steam-consumption test is being carried out, and not an efficiency test of a complete plant, to pass the measured feed-water through economizers. Should the latter course, owing to special conditions, become necessary, a careful examination of all economizer pipes would be necessary.