Plumbing and Ventilation 2: How to Remove and Replace Plumbing Fixtures

There are times in home improvement when the home owner must replace a plumbing fixture or at least remove it. I'm referring to removing the toilet, removing the bathtub and sink faucets or just removing a valve stem to replace its washer.

Home Improvement: Removing The Toilet

Let's start with removing the toilet, which should be removed if the toilet leaks at the floor (it's possibly the wax seal) or if the toilet is plugged and the pipes need cleaning with a snake or you are replacing the flooring in the bathroom with tile, vinyl, hardwood, etc.

Ever wonder why there are so many names for our favorite plumbing fixture? When removing any plumbing fixture, first turn off the water. The commode (from the Southern US) should have its own shut off down near the floor, offset to the left of center. This shut off should be equipped with a 3/8" OD (outside diameter) compression fitting for a 3/8" supply tube or closet riser (from "water closet", UK). Most modern heads (toilet) are designed for this size riser. If the one you have is an old 1/2" OD riser and shut off, better change it. For 1/2" nominal copper pipe coming out of the wall, I prefer a 1/2" nominal (5/8" OD) compression fitting in the shut off with a 3/8" OD compression fitting for a riser coming off at a 90 degree angle. If the 1/2" copper pipe comes from the floor, get the same thing but a straight shut off. If your house still has galvanized pipe, there are shut offs for sale to adapt to this style as well.

Okay, the toilet shut off is turned off. Flush the crapper (from Thomas Crapper, who held the early patents for a flushable toilet.). There will be a bit of water left in the toilet tank and the toilet bowl. A wet/dry shop vacuum works great to get the last drop out of both. Remove the nut on top of the shut off around the riser tube. This riser is also attached at the toilet tank with a large plastic nut. One or the other should be removed.

At the bottom of the throne (toilet) are usually two bolts (or three for some) found under the plastic or porcelain covers. Remove these covers and remove the nuts and washers below them. Now lift the toilet bowl and toilet tank together by lifting under the toilet bowl (don't lift under the toilet tank). There will be a bit of suction felt as the wax seal comes apart. No smoking during this procedure, there is sewer gas in the pipe, which is flamable. Place the toilet on a piece of cardboard, plywood or poly sheet, not on the carpet. Before replacement, tip the toilet bowl back on its back so it's resting on the toilet tank. Be very gentle with this thing, it is made of porcelain and like china is very fragile. Clean off the horn where the wax seal goes. Have a new one ready when you replace the toilet. Notice the floor flange; it probably is plastic (if your plumbing is recent) to attach to an ABS pipe or it is brass to attach to the old lead pipe—part of the cast iron system. Clean the old wax off the floor flange, so you can inspect it to see if it is cracked or not and to see if it is attached to the floor securely.

Get a large wad of newspapers or a rag and stuff it into the hole to eliminate any sewer gas and associated smells coming up into the house. When ready to reinstall the john (toilet, but I don't know where that term came from) and the bottom is clean, install a new wax seal with flange, also called a Kant Leak wax seal. You can either put the flange down into the floor flange or the wax side up into the bottom of the toilet. Pick the toilet up by the bowl again and carefully line it up with the closet bolts sticking out of the floor flange. Gently lower the unit onto the bolts and put your weight into it, mashing the wax seal down as it gets closer to the floor. Rocking the toilet back and forth helps, too.

Replace the washers and nuts in the opposite order they were removed. Tighten the nuts just snug, so there isn't any movement from the toilet and replace the nut covers. Replace the nut on the supply tube, either the 3/8" compression nut on the shut off or the plastic nut at the toilet tank. There you go, that wasn't that hard was it?

Home Improvement: The Bathtub and Sink

To remove the bathtub and sink faucet, pry the small plug out of the center of the faucet handles to remove a screw holding the handle on, then unscrew the trim behind the handle. Eventually you will uncover the rough-in part of the control. To replace this with a new one, the entire unit must be replaced. Each new unit has very good instructions with diagrams, so I won't go into those. For the single handle control, remove the plug again in the center of the control handle, which conceals a screw to remove it. The large round trim can then be easily removed by unscrewing the two screws holding it in place. To remove the bathtub spout, either unscrew it like a large nut, or look under it for a hex head set screw, which holds it on.

To remove a valve stem to replace its washer, turn off the water at the shut off or at the main, depending if it is for a sink, bathtub or shower. Remove the handle as mentioned above. Use an adjustable wrench to remove the nut directly below the handle. After the nut is free, take the handle and put it on the stem and open the valve as if turning on the water; the stem should come right out. Notice the rubber washer at the end of the stem held in place with a brass screw. Remove this washer and replace it with an identical one, that is a flat if it was flat or a bevel it is bevelled. Check the o-ring or packing to make sure it doesn't need replacing while the stem is out. The washer prevents water from going out the spout and the o-ring or packing prevents water from coming out the end of the stem around the handle when the water is turned on. If you have a problem getting your trim off, send me an e-mail and describe your particular fitting to me and together we should be able to work it out.


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