Kohler toilets are known as reliable and durable products. However, some consumers have reported problems flushing Kohler toilets. To save water, lower flow toilets have been mandated and implemented over the last few decades. There were 7.0 gallons per flush (GPF) toilets, then 3.5 GPF toilets and now 1.6 GPF toilets (Terry Love's consumer toilet reports). The low flow toilets are usually the ones with the problems. These new standards were implemented by the Environmental Protection Agency (EPA) for environmental reasons, but they don't necessarily coincide with good plumbing standards.

Flushing Toilet
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How a Toilet Flushes

The flushing of a toilet is not a mechanical process and there is no electricity involved; it is accomplished with "siphon power." As water fills up the toilet bowl, it overflows into the exit pipe and creates a vacuum that sucks out the remaining water behind it--similar to siphoning gas through a hose. The back of the toilet or the "tank" holds water, and when the water is released into the toilet bowl, the siphoning action is initiated. You can flush a toilet by dumping a bucket of water into the toilet bowl, it really does not matter where the water comes from as long as the toilet bowl is filled enough to cause water to overflow into the exit pipe and create the vacuum.

The Tank

The moving parts of a toilet are located inside the water tank. The flush handle on the outside of the tank is connected to the chain inside the tank, which is connected to the flapper/stopper on the bottom. When the exterior handle is pushed down, the chain inside the tank is pulled up and the flapper/stopper is lifted allowing the water from the tank to flow into the toilet bowl for the flush. After the water runs into the toilet bowl the flapper/stopper settles back down onto the flush valve. The fill valve is then opened and the tank refills with water. There is a float device inside the tank that rises and lowers with the water level. When the float valve is below a certain level, it opens the fill valve allowing water from the water pipe into the tank. When the float reaches a certain level, it closes the fill valve. If any of these internal part are not set properly, there will be problems flushing the toilet and adjustments will be necessary.

Common Problems Flushing a Kohler Toilet

Most problems flushing Kohler toilets do not come from the toilet bowl itself, unless there is a crack in the toilet bowl or an object that has been dropped into the toilet bowl and is caught in the exit pipe. Most other types of problems develop in the tank and involve the chain, the fill valve, the flush valve or the float device.

The Fill Valve

The fill valve can leak letting excess water into the tank, which then runs down the overflow tube into the bowl. The water will trickle continuously into the bowl, which wastes water. This will not necessarily affect the flush but will affect the efficiency of the toilet.

The Flush Valve

The flush valve can leak letting water run into the bowl and the water level in the tank to drop to where the fill valve opens periodically to refill the tank. This again wastes water, but also does not affect the flush. If the toilet is flushed at a time when the tank is not full, there may not be enough water for an effective flush and the waste may not be removed.

The Float Device

Similar problems can result if the connections inside the tank are not adjusted properly. For example, if the float device is not set properly, it can cause the fill valve to close too soon not allowing enough water into the tank for a proper flush. By adjusting the float device, more water can be allowed into the tank for a better flush.

Simple Science

The new standards mandated by the EPA can cause problems flushing. When the waste is not completely taken away, a second flush is necessary. Also the toilet can become clogged more easily because the low flow of water does not have enough force to carry the waste all the way out to the sewer. Irrespective of the EPA standards, a certain amount of force from the water flow is needed for the toilet to work properly. If you do not have the flow necessary you will need to adjust the float to allow more water into the tank for a better flush or the toilet will not flush properly. It is a matter of science (physics).