Have you noticed water dripping around your furnace or pooling up on the floor around it? This issue is fairly common with high-efficiency condensing furnaces, and it generally indicates that there is an issue with the furnace’s condensate drain system.

How Your Furnace’s Condensate Drain System Works

Conventional furnaces should never leak because no water forms inside them. With a high-efficiency furnace, the primary and secondary heat exchangers capture much more heat from the combustion gases. This leads to the gases being much colder when they exit the furnace.

When natural gas burns cleanly and fully combusts, it produces carbon dioxide and water vapor. In a conventional furnace, all of the water vapor is vented out of the house through the exhaust flue. In a high-efficiency furnace, the combustion gases cool down to the point that the water vapor condenses into liquid inside the furnace.

The condensate drain system in a high-efficiency furnace functions to capture the water so that it can drain outside or into your sewer system. High-efficiency furnaces have a drain pan that catches all of the water. The water then flows out of the drain pan into a series of PVC pipes that either lead to a floor drain or directly outside.

What Can Cause a High-Efficiency Furnace to Leak?

If your high-efficiency furnace is leaking, it usually means that one of the PVC drain pipes or the outlet in the drain pan is clogged. Algae, mold, and slime will often form inside the drain pan and pipes, which can lead to the condensate drain system clogging over time. If the system clogs, the drain pan will eventually fill up to where water starts to overflow and leak out of your furnace.

High-efficiency furnaces can also leak because the drain pan is damaged and has a hole in it or because one of the drain pipes is broken or has a loose joint. The only way to know for sure is to have a technician inspect your furnace.

Cleaning a clogged condensate drain system is typically not something you can easily do on your own. However, it is easy to prevent the system from clogging by having your furnace maintained every year, as the technician will always inspect and clean out the drain pan and pipes.

If you have a furnace that’s leaking or need any other heating service, you can count on the team at David White Services for help. We offer professional furnace repairs and maintenance, and you can also turn to us for all of your air conditioning and HVAC installation needs. Give us a call if you have any questions or need any HVAC service in the Athens or Lancaster areas.

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