Here is the old shower head showing the pipe coming out of the wall, the flange that covers the uglyness of the drywall cut the pipe comes through, and the nut where the shower head is screwed onto the pipe.
Fixing this should be a piece of cake; right? Buy a new shower head, unscrew the old one, screw on the new one and you are done. They are all a standard size and have the same thread pattern so you can't even get the wrong part.
Old system with the flange pulled away from the wall
Here you can see better how the pipe is screwed into the inside the wall plumbing. If you click the picture (or any of the pictures) you can see a much larger image that will show you the plumbing in this case is galvanized pipe. This is important because it gives you some idea of how much force (Torque/twist) you can use to unscrew the pipe without causing damage inside the wall.
You would not be the first person to snap off a CPVC or other kind of pipe inside the wall while trying to unscrew the shower head. That's how you convert a cheap & simple shower head repair into an expensive professional plumber job.
Old shower head attachment
Here is a closeup of the threaded joint where the old shower head is attached. The compound covering the threads is the old caulk/lubricant used to make it easier to tighten the shower head so it doesn't leak.
I don't know what was used, but it is now hard as a rock. It doesn't leak, but it isn't going to unscrew easily either.
If you look closely where the nut is screwed onto the pipe you can see several lines in the metal and a place where the chrome is scraped off. This is what happens when someone put to much force onto an unpadded pliers when they were screwing this on. It doesn't matter if we scrape the old one up some more while we are taking it off, but you don't want to do that to the new one.
Chrome scraped off
These shower pipes are not very strong and have a thin layer of chrome on their surface. It is easily scraped off.
Channel Lock pliers
These kind of pliers work well for screwing and unscrewing pipe that doesn't have flat surfaces for a wrench. They come in all sizes, can be adjusted over a wide range of openings and work well.
Keep in mind that even someone with little forearm strength can apply tremendous pressure with one of these.
Other side of the pliers
You can see the grooves the one handle slides in that control how far open the pliers goes. You will get the maximum holding power if you put the pipe you are trying to turn as far into the mouth of the pliers as it will go. You should have the pliers adjusted so when it is tight on the pipe the handles are as far apart as you can comfortably hold in your hand.
The holding power of pliers like this, as well as pipe wrenches depends on the direction in which the force is applied. In this picture you will have maximum gripping power when you push down on the handle. If you want to turn the pipe the other way you should put the wrench on from the other side. If you try to push up on the pliers handle in the position shown here it will slip and not hold well.
Teeth on the pliers
As mentioned above, the teeth on the pliers are cut so they point slightly to the rear and grip best when the pipe you are trying to turn is pulled into them by downward force (when positioned as in the picture) on the handles.
Not sure which way to turn the pipe to unscrew it?
If you are standing in the tub looking at the shower head and you want to unscrew it, you want to turn the pipe counter-clockwise. There is an old saying "Clockwise is lockwise." which may help you remember.
It's really frustrating when you realize you have been tightening something you were trying to take apart.
Galvanized elbow from the wall
After the pipe is removed you can see this is a galvanized iron fitting in the wall. Seeing this you can be almost certain it is a 90 degree elbow attached to more galvanized iron pipe that goes down to the mixer assembly.
I will warn you that you can't be certain that is the case!! People do amazing things when they are short of money, don't know better and/or know any problems will be hidden behind the wall board.
Part of the reason repair bids come in high is you never know what you will find when you open up the wall. What should be a simple job can suddenly become much more difficult and expensive because of errors in the previous work.
My plan was to use two of these pliers to unscrew the old shower head from the pipe. I wanted two so I could hold the old pipe in place while I unscrewed the shower head. I wanted to avoid twisting or pulling on the pipe in the wall as much as possible. You never know how rusted, corroded and/or weakened the pipe in the wall may be. The more gently you can treat it the better.
To keep from scratching the pipe I pulled an old sock over the whole length of pipe as padding. It is not as easy as you might think to pull two wrenches in opposite directions without twisting them in other directions at the same time. In this case the pipe started to unscrew from the wall before there was any movement of the shower head connector.
Looking back I guess I could have tried to unscrew the shower head from the pipe after I had it loose from the wall. That would have saved me a trip to town for parts. At the time I was confident I would probably twist/scrape/wreck the pipe trying to do that. It seemed easier to get new parts.
The replacement parts are a standard item
It was a pity the clerk helping me didn't know that. The plumbing parts at the Home Depot I went to are located at the back wall. This is standard merchandising 101. Make the customer walk past all the more expensive stuff on their way to the cheap low end things. It's an approach I find less and less helpful as my hips wear out.
I found the 40' wall of parts and went up and down several times. There were drain parts, faucet parts, toilet parts, etc., but no shower parts.
I stopped an unlucky clerk on her way to her break and asked for help. After she went back on forth on the row a couple times I realized she doesn't know this is a standard part. Fortunately, I had brought the old one with me so she took that into the break room and ask someone there where shower parts were. She went off to find them and came back in about five minutes announcing success. For some reason all the shower parts were on the end cap of another row about 60' from where we had been looking.
Pipe thread compound
Some people wrap Teflon tape around the threads before screwing them together. This reduces friction which makes it easier to screw the pipe together tightly enough to prevent leaks.
I personally prefer Rectoseal. Think of it as finely ground Teflon in a grease-like mixture. It sticks well, and has always made a good seal when I have used it. It is safe for use on pipes of all kinds and doesn't harden over time. I may want to be able to remove the shower head I am about to install at some time.
Rectorseal is brushed on
The Rectorseal is brushed on with the applicator that comes in the bottle. You don't need much, the excess will just squeezed out. It makes the pipe very slippery so it is easier to turn it tight.
You can see I have only painted on a little of it.
The new pipe is in place
Here you can see the new pipe after it has been screwed in place. I was fortunate. With the lubrication from the Rectoseal I was able to tighten the pipe without using any tools. The bend in the pipe makes it a wrench of sorts and when I turned it as tight as I could I thought it was probably as tight as it needed to be.
This is not something a novice would be able to do. I have tightened a lot of pipe and you gradually get a "feel" for when it is tight enough. I also made sure to check for leaks when I fired up the new shower head for the first time.
Tightened into the wall
You can see the Rectoseal squeezed out around the fitting. That tells me I had plenty on the pipe.
If I had been thinking a little faster I would have slide that flange onto the pipe BEFORE I lubed the threads! Not a big deal since it wipes off easily but if you are a contractor working against a time deadline things like this slow you down.
Ready for the shower head
So, after spending $12 on parts, a trip to town, and a couple of hours this simple job is almost finished.
One of the reasons I was never a success as a contractor was that I could not look someone in the eye and quote $250 plus the cost of the shower head for a job like this. It's what it takes to make money, but seems outrageous.
The new shower head
My wife bough a fancy shower head as the replacement. We frequently have grandkids in the tub these days and she wanted a spray head on a flexible hose to make it easier to wash heads.
The nice thing about better parts is how they are made. As you can see here, this one includes a gasket which will make a seal easy
With new and well lubricated threads plus a rubber gasket I figured I could get by with gently tightening the shower head. I didn't use padding and was able to tighten enough without leaving marks.