Plumber Training: 5 Most Common Toilet Issues (+Troubleshooting Tips)

Whether it's an overflowing bowl or something very odd flushed down the drain—toilet troubles are often a source of embarrassment, stress, and frustration for homeowners.

Many of your future clients will try to troubleshoot (or simply ignore) their malfunctioning toilet until it becomes a genuine emergency, or simply too annoying to bear.

What kinds of issues can you expect to deal with most often after plumbing training? Here are your top five most common toilet problems and the causes you'll investigate first when solving them.

1. Clogs

Ah yes—the dreaded toilet clog. In many cases, by the time you're called in to help, your client will have already tried to resolve the issue with several DIY tactics. These typically include pouring harsh drain cleaner into the bowl, using whatever plunger they had on hand, and perhaps repeatedly attempting to flush the toilet (which likely made a bad problem much worse).

During the course of your plumber training and apprenticeship, you'll encounter many different causes of toilet clogs—ranging from the mundane to the ridiculous! These are two of the most common culprits:

  • Hard water deposits that have built up over time and are interfering with toilet functionality

Your go-to tools for removing a clog will be a flanged or accordion plunger and an auger. In some cases, you may need to remove the toilet and snake the sewer line—see this post for a step-by-step video of how this is done.


2. A Weak & Incomplete Flush

The client will tell you that their toilet takes a long time to flush, and rarely flushes completely. They probably have to flush it several times after each use—which is clearly a waste of time, not to mention water!

One of the top causes of this very common problem is mineral build-up in the rim feed and jet holes of the toilet bowl. These deposits block water flow into the bowl, reducing the power of each flush.

Your solution? You'll need to clean the rim and feed holes of the toilet. Start by turning off the water supply and pouring a toilet bowl cleaner down the flush valve opening. Some experts suggest feeding a wire into the rim holes to scrape away mineral build-up and fish any waste out of the jet hole. Afterward, you'll let the tank re-fill and flush the toilet several times to clear out the leftover cleaning solution and debris.

If mineral build-up isn't the issue, you'll need to check the water level in the tank (and re-adjust it if it's too low) and make sure the flapper isn't closing before enough water is released to complete the flush.


3. A Constantly Running Toilet

This problem is both annoying to listen to and incredibly wasteful. A toilet that runs constantly can consume gallons of water in a 24-hour period.  Plus, it can be particularly damaging to septic systems.

There are a few common sources of this problem:

  • A chipped, eroded, or rough flush valve
  • A defective flapper or tank ball (which prevents a seal from forming and allows water to pass into the bowl)
  • Faulty flush lever (if the chain is too tight or loose, the flapper can't function correctly)


4. A Leak Around the Base of the Toilet

Get an urgent call from a client about water gathering around of the base of their toilet? This problem demands immediate action so the dirty water doesn't damage the sub-floor and contaminate the living environment.

Here's what you'll troubleshoot first:

  • Check the tightness of the "tee bolts" which secure the base of the toilet to the floor
  • Verify that the wax ring (the seal between toilet and floor) has not been broken
  • Check the toilet base for cracks
  • Make sure the "leak" isn't really just condensation forming on the tank (you'll need to check the ventilation and possibly use a toilet liner to solve this issue)


5. The Toilet Won't Flush At All

The most common cause of this problem is a poorly seated flapper. If your client pushes the handle and nothing happens, chances are the flapper is worn out, or something is preventing it from sitting securely in place (the chain may have come loose or gotten stuck under the flapper).

If this fairly obvious culprit isn't the source of the issue, these other malfunctions probably are:

  • The linkage pipes that connect the handle to the flapper are broken (if these are damaged, the flapper won't budge, no matter how often the handle is pressed)
  • The flapper has deteriorated
  • The overflow tube is cracked

And there you have it! Some of the most common toilet troubles you'll get called on to fix after plumber training.

Haven't started pre-apprenticeship training yet, and looking for a top-rated plumber program in Toronto?

Have a look at the pre-apprenticeship plumber training offered by Herzing College. An admissions advisor can answer all your questions about courses, costs, financial aid, and how to apply.

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