What To Do When Your Toilet Doesn't Completely Flush

One of the most unpleasant plumbing problems to face is a toilet that won’t flush all the way. Not only is it highly inconvenient, but it also presents a sanitation hazard. Everyone takes their toilets for granted — but when they’re not working as they should, what can you do? Read on to find out.

Narrow Down Possible Problems

When a toilet doesn’t flush completely, there could be any number of causes. Start by checking the toilet tank. If the toilet tank doesn’t fill all the way, you’ll need to figure out why and fix that problem. If the tank is filling properly, then you may have a clog, or there may be other issues at work.

Another easy thing to check is the toilet’s chain and handle. If the handle doesn’t do anything when you press it — in other words, if it swings freely — that’s a sign there is a problem with the handle itself or the chain that connects it to the flapper. Check inside the toilet tank, and if you find the chain or handle is broken, replace them to get your toilet back up and running.

Clear a Clogged Toilet

A clog is the most common reason for a toilet that doesn’t flush. Clogs can range in severity, from a complete blockage to a partial obstruction. Wipes, toilet paper and other items can build up in sewer lines, which could result in slow flushing that doesn’t completely clear the bowl.

To remedy this problem, use a plunger or toilet augur. If using a plunger, make sure it’s a flange-style so that it seals well with the bowl. Use the plunger a few times to loosen any materials potentially clogging the sewer lines, then flush the toilet to see if it’s working better. If the flushing improves, you may need to use the plunger once or twice more to completely clear the blockage.

If using a toilet augur, follow the manufacturer’s instructions for use, then flush to see if the situation has improved.

If you have neither a plunger nor an augur handy, you can also try hot water. Sometimes this is enough to loosen mild blockages. However, never use boiling water as this can damage the toilet or its seals.

If none of the above methods work, you may not have a clog. Below, you’ll find some other issues that can cause a toilet problem.

Check the Flapper

Flappers are at the bottom of the toilet tank. They should seal tightly when closed. If they don’t seal completely, it can affect the way your toilet flushes. Remove the tank lid and examine the flapper to see if it is sealing properly. One way to check is to listen for a toilet that runs often. This is a sign that water is draining from the tank even when the flapper should be closed. If you spot an issue, then you’ll need to pick up a new flapper at a local hardware store and follow its instructions for installation.

Check the Inlet Holes

When you flush the toilet, water drains from the tank through small inlet holes around the underside of the toilet bowl’s rim. If these are clogged, then the water will drain sluggishly into the toilet bowl, resulting in a slow flush that doesn’t clear the bowl. Look for these signs to determine whether inlet holes are clogged:

  • Your tank drains slowly when it flushes.
  • Water flows into the bowl straight down from the rim, rather than in a diagonal direction.
  • You can see areas in the bowl where water isn’t flowing at all when you flush.

Each of these signs could indicate clogged jets. Use a scrubber, brush or toothpick to clean mineral buildup from the jets to get the water flowing again.

Check the Overflow Tube

An overflow tube is the tube in the center of your toilet’s tank. It’s meant to drain excess water into the toilet bowl should the tank overfill. With time, the overflow tube can develop cracks, which could cause the tank to constantly drain water into the bowl. This lowers the level of water in the tank, which results in slow, sluggish flushing. If you spot cracks in the overflow tube, replace it.

Check the Fill Valve Assembly

If your toilet doesn’t completely flush, the problem could be the fill valve. Start by checking the fill valve’s float. Depending on the style of the valve, this could be a bulb on the end of a metal rod, or it could be a circular float that fits around the fill valve itself. The float is designed to shut off the fill valve when the water reaches a certain level in the tank. If the float is improperly adjusted or if it has become stuck, it won’t rise when the water level rises, which could result in an underfilled tank and poor flushing.

Underfilling can also happen if the fill valve itself is clogged. To check this, flush the toilet so that water drains from the tank, then watch the fill valve to see if water is flowing from it as it should.

Check each of these things, and you’re likely to find the reason your toilet doesn’t flush well. If none of these solutions fix the problem, you may need to call in a professional — or possibly upgrade your toilet. For the best in new toilets, be sure to shop the selection at Modern Bathroom.

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