Q: Can you educate me on all the parts of a toilet and how they work? Now that I have my first home, I need to purchase toilet replacement parts and am clueless. My toilet appears to be fairly standard-looking with a rectangular tank that rises up from the bowl. Do you think I'll be able to replace parts easily, or will I have to call a plumber? Money is tight now, so I'd love to be able to tackle this myself.
A: I've never thought of myself as a toilet professor, but as a master plumber as well as a builder, I've put in my fair share of toilets. Most toilets have similar parts, as the function of activating the flush is pretty standard. The parts may look different, but they do the same thing.
For sake of discussion, I'll be describing a toilet that has a tank that stores water in it for the flush. (Commercial toilets don't typically have tanks.)
Let's start with the china parts. Usually when you purchase a new toilet you get three parts: the bowl, the tank and the tank lid. The most common toilets are made from clay that is fired in a kiln. The visible parts are coated with a clear glaze that's close to the hardness of glass. This glazing allows toilets to be cleaned fairly easily. You should never clean a toilet with an abrasive cleaner, which will scratch the glaze and dull the appearance.
The toilet bowl has two important aspects. The water enters the bowl through a large hole at the top rear of the bowl. The moving water goes into two places: the small holes in the underside of the bowl rim and into the syphon-jet hole at the bottom of the bowl. You'll have to peer inside the bowl to see these (use a mirror to see the rim holes).
A forceful flush happens when the water from the tank rushes quickly into the bowl. Water passing through the syphon-jet hole pushes water out of the bowl into the drain line in the floor. Water that passes through the rim holes is supposed to wash the sides of the bowl.
Water enters your toilet through a shutoff valve connected to a water line that either comes out of a wall or up through the floor. A flexible line pipes water between the valve and the bottom of the toilet tank.
Inside the tank you'll see a menagerie of confusing parts. The two parts that cause the most frustration for homeowners are the fill valve and the flapper valve. The base of the fill valve connects to the flexible water supply line. The flapper valve connects to the giant hole that's in the bottom of the tank.
In the past 30 years there's been an engineering revolution with both valves. Old toilets had a float ball that connected via an arm to the fill valve. You may still have this type. Newer ones have the float ride up the center core of the fill valve. These newer valves almost always provide a full-flow fill until the water shuts off. Older valves were plagued with whistling noise as they aged.
The flapper valve is typically a round disc that's connected to a chain attached at the other end to the flush handle trip lever. When you push down on the handle on the outside of the tank, the flapper valve lifts, allowing the water stored in the tank to rush into the bowl. It's that simple!