hvacplumbing
As you can see below, I broke the drain line off flush with the wall. There appears to be either a union or an elbow embedded in the wall with a broken off piece of pipe in the fitting. The joint appears to be glued because I can't remove the little fragment of pipe that is left behind. What are my options for fixing this? Right now the water is dribbling out of the broken pipe and running down the side of the house instead of being discharged from the end of the pipe two feet from the wall.
Unscrew the white compression nut and take a look at the sealing ring that is under it. These can get hard with age or over compressed and lose shape and thus lose its ability to squeeze tightly to the down drop pipe from the sink drain. If this is the case it is an indication that the sealing ring needs to be replaced.
The common type of the sealing ring is made of a nylon material whilst the orange colored one (purchased at big box store) is made of a more rubbery type plastic that will compress and squeeze much better under the compression nut. (In the picture I have cut the nylon part to show it's wedge shaped cross section). I have also seen the rubbery type wedge rings in a blue color as well. These better rubbery sealing rings cost more than the nylon types but are far superior in my opinion.
When you take apart the slip joint do take care to clean out the joint and the outside of the drop pipe to remove any old drain gunk and soap scum. A nice clean setup will result in the best seal of the wedge shaped sealing ring against the drop pipe.
Heat both parts moderately and safely (ie, don't set the house on fire) concentrating on the Tee or outside part.
Then apply ice to the pipe (ie, the "inside part" of the joint.)
This is usually a more practical (and less frustrating) approach than trying to heat one and cool the other at the same time.
The idea in play is to expand the outer part and shrink the inner part to aid in separating them. It won't always work, but it's what I'd try first when simple disassembly fails.
Heat may also help to break up the corrosion more directly by driving water out of it.
Best Answer
However you end up fixing this do plan to use a more repairable solution that used by the original installer. It is an insane approach to cement or stucco in a glued plastic fitting like this. As a minimum the part that gets cemented in place should be made out of metal with brass or bronze being preferred over an iron type fitting. The outside pipe should be fitted to the cemented in part via a threaded connection.
If you must repair this with minimal disturbance to the cement or stucco, (its hard to tell which from the picture) then I would see a number of possibilities...
a) Work at drilling and carving out the glued in inner pipe piece bit by bit till you get it the point where you can fit a new piece of pipe in its place. You have to use much care for this because the process could put excess torque on the remaining pipe in the wall and lead to possible further breakage.
b) Try to find a suitably sized pipe thread tap and cut threads into the inner diameter of the pipe stub. Once this is done you can fit it up with the proper type of barbed brass pipe nipple fitting. To this you can attach a flexible piece of hose to go out the 2 to 3 feet from the foundation.
If you have access to the area inside the wall you may be able to simply pull the existing fitting out of the cement and install a newer more suitable type of exterior transition that the method used.
If the wall is stucco you could take a chisel to the area around the broken off fitting and enlarge the hole enough to get access to the pipe. Then you can fit up the proper type of pipe fittings and re-patch the stucco around a metal transition fitting. Stucco patching is a fairly straight forward task and should be able to completed successfully by a diligent DIY home owner.