Why Does My Toilet Drain Slowly

When a toilet is in good shape, pressing down the flush handle will normally cause water to quickly flow down from the water tank to the bottle and down the drain line. It is important for water to move quickly because this action creates suction pressure in the pipe sucking down the waste. However, there are problems with slow flushing toilets. This inconvenience might drive one crazy as it most often leads to incomplete flushing.

Slow flushing might be as a result of problems with the water level in your tank, clogged pipe or toilet itself or accumulation of hard minerals or calcium. A sluggish toilet shouldn’t be left untreated as ignoring this problem may lead to total toilet clogging which is not only annoying but also dangerous.

Water Level in the Tank

This is the most causative reason of slow flushing toilets. If the water level in the tank isn’t up to the required level your toilet’s flushing power will be poor. This is so because a high water level adds more force intensity which is mandatory for complete flushing. However, if the water level in the tank is not up to the recommended level your bowl might not be clearly emptied. Ensure that the water level in your tank is sufficient by filling it to approximately a half-inch below the overflow pipe.

Clogged Pipes

Drain buildup is another major reason to slow flushing toilets. To determine whether the drain is clogged, pour a gallon of water into the bowl swiftly; if the water level in the bowl rises quickly then there is a clogged problem somewhere. To fix this, use a dandy plunger to try and unclog it and if it doesn’t work snake the line.

Mineral Buildup

If your toilet drain is clear and free and your tank is full, slow flushing might also be due to mineral build-up in the jet holes of your toilet. Minerals such as calcium might be collecting in these jet holes every time one flashes the toilet. These mineral buildups reduce the flash power as they cause the pressure to become less and less powerful. To fix this use a mineral remover together with a metallic tool to clear out the holes. However, if there isn’t significant buildup but your toilet still has a flushing issue, call your trusted local plumber to check it out.

Remedies for Slow Flushing Toilets

1. Use a fitting plunger to plunge the toilet. This process is easy and in case the slow flushing was due to a partial blockage by probably waste, plunging will remove it. However, in case the toilet is showing some other signs of blockage, for example, backing up, if plunging does not work use a toilet auger to clear the blockage.

2. If the toilet continues to flush slowly even after plunging, listen to gurgling sounds in nearby pipes. If you hear such sounds, then it means there is not a sufficient amount of air in the pipes lines to enable water to flow freely. This might be because of debris clogging the vent pipe. Clear all the debris from the roof vent opening, after clearing the opening, use a garden hose to spray some water into the pipe. In case the water backs up, use a sewer auger to clear the vent.

3. Check the working mechanism of the toilet to make sure there is a quick flow of water from the tank to the toilet bowl. Start at the flashing valve, open the tank and keep an eye on the flapper when flushing, the flapper should rise when the valve has been pushed down to an almost vertical position. In case it does not, it is probably preventing water from quickly flowing out of the tank. Consider shortening the chain holding it to the valve.

4. Remember the water level in the tank should be approximately half an inch below the overflow pipe when the tank is full. If the water is below that level then there won’t be complete flushing.

5. Clear the water inlet jet holes around the toilet rim. The holes might get blocked with mineral deposits from the water such as calcium more especially if your toilet is old or you are using hard water.

Things You Will Require

• Garden hose
• Plunger
• Ladder
• Sewer auger
• Toilet auger
• Paper clip


• In case the toilet is still showing signs of slow flushing even after you have tried these procedures, then something might be stuck in your toilet’s P-trap, something like a metal or even plastic toy and using a toilet auger hasn’t worked, you might pull the toilet to have the object removed.
• In case you have trees planted around the house and you have noticed the slow flushing problem worsening with time, this might be because roots might have grown into the sewer and this will require professional intervention.

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