What issue can cause a pressure buildup in a vented condensate tank?

In the context of a vented condensate tank, a pressure buildup can occur when steam traps are leaking. Steam traps are designed to allow condensate to drain from the system while preventing steam from escaping. If a steam trap is leaking, it can cause steam to enter the condensate return system inappropriately. This influx of steam into the condensate tank can increase the pressure, especially if the tank is vented improperly or if there are restrictions in the venting system.

This condition not only hinders the proper function of the condensate drainage system but can also lead to safety issues, including potential damage to the tank or associated piping. Maintaining properly functioning steam traps is crucial for ensuring that condensate is managed effectively and pressure is controlled within the system.

The other options present scenarios that relate to the operation of a condensate tank but do not directly cause a pressure buildup in the way that leaking steam traps do. An overfilled tank might lead to overflow issues but would not necessarily cause pressure to build up. A blocked discharge valve would prevent proper drainage but primarily lead to higher liquid levels rather than steam-related pressure increases. Lastly, faulty boiler operation could affect steam production and system efficiency, but it does not specifically relate to pressure issues within