I have a heater / ac unit in a utility closet located in the garage. My problem is the pvc condensation line that runs along the wall to the outsidce of the house is leaking about 4' from the unit. The pipe runs from the unit about 3' then drops down to the bottom of the the garage floor and then runs along the perimeter of the garage and then runs outside to the front yard. Last year i cut into the wall and noticed a crack in the pipe where a nail had been driven into it. i fixed the pipe and ran pressurized water through it to test it it before i replaced the sheet rock. I still have the same problem, no leaks through pressure (garden hose), but the pipe is totally covered in condensation. What can i do to get this condensation under control. The pipe has no obstructions what so ever and is insulated to the point where it enters the wall from the unit.

Thanks

 

macinar,

Condensation will be forming on the outside of the pipe because it is not insulated.
You will need a closed cell type pipe insulation and this type must extend where the pipe passes through the wall.

 

Thanks for the reply, just to check, i currently have the pipe wrapped with insulation before it passes through the wall, don't know what the proper name is bit is the black slip on , peel and stick type. Is this the right kind?

Thanks

 

I believe what you have is called Armaflex ( a firm foam insulation) and that is the correct stuff. Good luck.

 

Majak is right that Armaflex is the name of a high quality commercial pipe insulation.
This type comes as a solid tube and must be split, put on the pipe and then glued closed.

The type that is peel and stick is the type available at building centers and is just referred to as foam pipe insulation.

This peel and stick kind would work fine but if you have plastic pipe you must be carefull to get a size that matches the pipe size.
This foam is usually sold in standard pipe sizes.

 

ok so since there are no leaks in the pipe and the pipe is insulated what else can be casuing the condensation?

 

By this I take it to mean that the full length of the pipe is not insulated.
If you say that it is condensation leaking I assume you mean that moisture is forming on the outside of the drain line causing it to drip.
Or, are you mixing up terms here and mean water that drips from the coil and runs out the drain. This is called condensate.

If moisture is forming on the surface of the pipe you need to install foam insulation on the full length of the drain line.
It must start at the beginning of the drain line at the furnace and run, uninterupted to the outside of the house.
This foam insulation must be a snug fit on the pipe, not sloppy. Also, you must seal the ends of the pipe to prevent moist air from getting in between the pipe and insulation.

Or if it is not condensing and dripping off the pipe you may indeed have a cracked pipe or something similar.

If you still are not sure and are able, you could find a place to host a picture of what you have there and link us to it.

 

Thanks Greg,

There was in fact a cracked pipe that i repaired, but what is occuring now is condensation on the outside of the drain pipe. I have it wrapped with insulation from the unit all the way to where it goes into the wall, but it is not wrapped throughout the entire length. If i had to insulate the whole pipe, that would mean tearing into 20' of wall. Yikes!!! I'll check the ends and seal them up as much as possible. By the way, the pipe drains fine. I have ran water through the line via a garden hose and experienceno leaks what so ever.

 

Glad you found the problem.

You could check the drywall at the bottom of the wall where the drain runs through and if you see evidence of moisture it could be from a dripping drain line.

 

Anytime we have a drain from the AC going to the outside . We take and just slip two pvc 90oL on the end there to make a trap like out there so no bugs get into it.

ED

 

Why not eliminate the pipe as a drain & install a condensate pump. They use 3/8" plastic tubing which you might be able to fish thru the existing pipe. The water usually has time enough to warm up before being discharged so as to eliminate condensation.

 

It could be that your condensate drain is on the positive side of the blower. If it isn't trapped deep enough, the blower could overcome the trap if too shallow and be constantly blowing AC through the condensate line to the outside of the building as well as cold condensate. This would chill the water and line enough to cause the line to sweat in the wall easily. If you decide to replace the condensate line in the wall, use copper and insulate it well, especially IN the wall. Since this is an ongoing concern, use 1/2" wall. The ends must be butt glued together as well as any turns. Make sure the trap is about 3"" deep before it enters the wall and has a clean-out at the bottom of the trap.