Hi,

is it a simple deaerator with no CO2 or NH3 beeing present?

If yes, it's not so difficult ... Please check:

https://www4.eere.energy.gov/manufacturing/tech_deployment/amo_steam_tool/equipDeaerator

http://chicago.swagelok.com/~/media/Distributor%20Media/C-G/Chicago/Services/ES%20-%20Correct%20Venting%20from%20a%20Deaerator%20Vent_BP_2.ashx?la=en

If you have NH3 and CO2 present it might make a difference in the amount of steam beeing condensed.

Best regards,

Gerhard

All of the extraction steam condenses in a deaerator unless you're venting, which should be a transient operation.

Usually, all steam extracted from the turbine should condense in the deaerator, unless if small quantities are exhausted accidentally with the uncondesable gasses such as oxygen, etc.