Gas and Oil Home Heating Furnaces - Water in floor vents/dripping off condenser

I have water, lots of water in my floor vents (duct). I opened the lower section of my heater to check the condenser (I thought it may have frozen up or something) water dripping off copper loops on edge of condensers. They are set up in an "A" kinda fashion. the pan had very little water in it. The drain was clear. There was a black mouldy looking coating on the fins. I cleaned it off with bleach and a baby hair brush (so not to damage the fins) I have approximately 1 1/2 inches of water in along a 40 foot run. I drained the water from the vent (this was nasty and I don't want to do it again) I can find no other source for the water than the condenser. What is probably wrong and can I fix it myself. My DH and I tend to be handy and not wealthy. PLEASE HELP :confused:

It sounds like your furnace and cooling coil is in a closet inside. Is this a mobile home? A slimy buildup on the fins of the cooling coil can cause the water to drip off instead of running down the surface of the fins to the drain pan. When cooling coils are dirty, the mess is beyond just what's at the surface. the dirt gets impacted into the coil. If you have a shop vac, try vacuuming along the fins with the bristle brush attachment. Usually, very dirty coils have to be removed and cleaned out in the yard with a commercial grade foaming action cleaner that's sold to the trade. This type repair job can be $$$. You could try washing otut he coil with some detergent and flush with a garden hose while sucking up the water with a shop vac-it's messy. I'm a little concerned that you mentioned the drain pan seems to have very little water in it. Inspect all along the bottom of the pan with a bright light to see if it's rusted thru. One trick I use is to mix up a batch of food colored water. Pour it in the drain pan being careful to not spill any. If you get colored water on the ducting, AND it's not spilling over, then the pan is probably rusted thru. I've even used milk for this trick. If the drain pan is rusted thru, the fix is to replace the cooiling coil/drain pan assembly- $$$. BTW- the indoor coil is the evaporator coil, although you'll often see me call it the cooling coil.

I am really concerned now as the drip pan is a plastic square (24 x 19 3/4) with the center open over the vent. The coil "A" rests with the edges in the pan and the opening underneath the "A" The plastic pan and coil seem to be attached to each other and if you push or pull the coil both will move just about 1/2 inch. Little if any water seems out from under it when we move it. DH crawled under the house and disconnected the 16 inch flex tubing connecting the two parallell 40 foot rectangular vent runs. So now essentially when I pour water on the coils most of it will run straight into the pan and out the drain pipe, but if I pour a lot of water it goes throught the fins and down to the ground.

Yes we live in a double wide mobile home (I do not recommend this to anyone who can afford a real house and I really hate floor vents)

Thanks for the quick reply as it is getting really hot here in Arkansas and four hot cranky kids on top of this mess is no fun.

I will try the food coloring and the shop vac and see what happens.

If the drain pan is plastic, we can rule out the pan being rusted thru. The drain pan and the cooling coil are all one assembly. Since you can see the ground from the A coil area with the duct disconnected, you can clean the coil in place. Take a spray bottle of 409 or similar and thoroughly spray down the coil. then flush it real good wth the garden hose. Repeat this several times. Maybe you can fashion a barrier out of cardboard to keep water from going into the ducts. Using the nozzle attachment on the shop vac hose, suck up all the junk that is in the drain pan and then flush out the drain line with the garden hose. Suck up any water that went into the ducts while flushing. Put everything back together and see what happens. Cleaning out the coil, drain pan and drain line should solve the problem. Take the kids to DQ. The soft serve takes care of crankiness.