Clearing a clogged condensate drain
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Photo 1: Treat the pan with tablets
Shove the tablets into the drain pan
opening and push them in farther using a dowel
or long screwdriver. Add new tablets monthly
during air-conditioning season, or less often if
you rarely use your A/C.
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Pan tablets are available at most home centers and plumbing supply stores.
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Photo 2: Install new tubing
Screw the new fitting into the drain pan and slide on the tubing. Route it to the floor drain and secure it with tubing straps.
When you see water puddling around the
furnace with the A/C running,
you have a clogged condensate
drain tube. Condensation
from air conditioning coils
contains bacteria that can
form slime and clog the condensate
pan drain tube. You
can prevent slime and eliminate
drain tube clogs in two
easy steps. First, remove the
drain tube and fitting from
your A/C condensate pan.
Toss them. Next, buy a package
of slime preventing tablets
(one choice is AC-Safe Air
Conditioner Pan Tablets; sold at
Amazon.com). Follow the
package dosing directions and
insert the tablets right in the
drain pan (Photo 1).
Next, buy a 3/4-in. MIPT
barb fitting, a small coil of
3/4-in. I.D. vinyl tubing, and
several tubing straps. Then
install the larger tubing (Photo
2). The pan tabs will reduce
slime formation, and the