Q: My bathtub faucet is leaking a lot. Usually, I just take off the faucet head and clean out the buildup of calcium and it takes care of the problem. I have done this so much the screw has dissolved and I can't get it out. How do I remove it? I'll have to replace the whole faucet. How do I do it? I probably should shut off the water right? It is a single handle. It slides straight out to turn on and twists for temperature. There is also an access panel in the wall. -B
A: At this point you have a couple options. 1) try to rebuild the faucet or 2) replace the entire faucet. Either way, it may be a little challenging and you will definitely need to shut off the water and release the pressure in the water lines by opening up another tap or two.
1) To rebuild the faucet you will need to the handle off somehow. You could either break it off, which would require you to buy a replacement handle, or drill out the screw to get the handle off. This handle will probably need to be removed regardless, of if you are replacing/rebuilding the valve. If you can drill out the screw, you can get the cartridge out of the faucet. If you can get that removed, take it to your local hardware store or home center to match it up with a replacement. Most common faucet brands and styles can be rebuilt with parts that are easily found. If you cannot find matching parts or get the cartridge out, you will need to replace the faucet. Rebuilding will likely be the least expensive and simplest fix for this.
2) To replace the valve, you will need to remove the handle and trim pieces on the shower wall side. This will allow access to the mounting screws that hold the valve in place. This is usually done by removing a couple Phillips screws. You are lucky to have an access panel to the back of the faucet. You will have 4 pipes connected to the faucet valve, one for the hot supply, one for cold supply, one for the tub spout, and one for the shower head. This is where things can get tricky. Getting the pipes off the valve may be difficult depending on how they were attached. Hopefully, most are attached with unions that allow the union to be disconnected without needing to turn the valve or the pipe. Sometimes, the pipes are soldered to the valve. If this is the case then you will need to cut the pipes and solder in couplers and unions to attach the new valve.
If you have further questions, let me know. It can be helpful to see a picture of what you have if you get a chance.