If a thermostatic steam trap fails in the closed position, what will happen to the heating unit?

When a thermostatic steam trap fails in the closed position, the primary consequence is that condensate cannot escape from the heating unit. As a result, the unit can become waterlogged. This is due to the accumulation of condensate, which displaces steam and prevents it from adequately heating the space.

Waterlogging can lead to a number of issues, including reduced heating efficiency and potential damage to the heating equipment. Condensate buildup can create an environment where steam cannot effectively pass through the system, leading to inefficient operation and possible operational hazards.

Understanding the role of steam traps is crucial in managing heating systems. They are designed to allow condensate to drain while preventing steam loss. A failure in the trap, especially in the closed position, disrupts this balance, leading to the situation observed in the context of this question.