What is the main concern regarding condensation in high-efficiency furnaces?

The main concern regarding condensation in high-efficiency furnaces is the risk of corrosion. High-efficiency furnaces operate at a much lower temperature than traditional systems, which allows for the production of condensation as the combustion gases cool down. This condensate, typically acidic due to its water content interacting with combustion byproducts, can accumulate in the heat exchanger and flue components. Over time, this corrosive condensate can deteriorate these parts, leading to reduced lifespan and potential failure of the furnace.

It's essential for these systems to have proper drainage systems to manage and expel the condensate safely. If not adequately addressed, this can lead to costly repairs and reduced efficiency of the unit as it ages. Thus, understanding the implications of condensation is crucial for maintaining the functionality and longevity of high-efficiency furnaces.