Furnace Exhaust Fan Full Of Water

Condensation from air conditioning coils contains bacteria that can form slime and clog the condensate pan drain tube.

Furnace exhaust fan full of water.

There should be no water involved with a standard efficiency furnace. Water may accumulate due to a broken silver bladder or faulty insulation. Look inside of the blower box for water accumulation. The fan assist is meant to help with the natural draft not pressurizing the exhaust pipe with a power vent fan found in condensing furnaces and discussed below.

A standard efficiency furnace extracts some heat from the combustion gases and quickly vents them out the exhaust or flue pipe. If there is water in the blower box contact a professional repairman to replace the blower box and silver bladder. As the exhaust gases cool down during the primary and secondary heat extraction water usually condenses and flows out of the furnace. First remove the drain tube and fitting.

You can identify a condensing furnace by the pvc vent pipe that allows exhaust gases to exit the appliance after they have cooled down. Water in condensing gas furnaces condensing furnaces also known as high efficiency furnaces are generally in the 90 to 97 efficiency range. If you have a condensation leak with a standard efficiency then its exhaust or flue pipe may be incorrectly sized. When you see water puddling around the furnace with the a c running you have a clogged condensate drain tube.

You can prevent slime and eliminate drain tube clogs in two easy steps. Avoid double trapping and vent the drain after the trap to prevent airlocks.