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How to Fix a Running Toilet


You would be surprised how much water a running toilet can waste. Fixing a running toilet yourself might be easier than you think. However, a plumbing and drain professional like iSky might be needed for bigger problems related to the sinks, faucets, showers, tubs, toilets, water lines and drains in your bathroom. Whether you hear water running continuously or it’s cycling on and off, here are some things you can look for when it comes to running toilet repair.

Check the flapper. It could be that the flapper is just stuck open or that it keeps getting caught on the chain. However, if the flapper isn’t sealing properly then a toilet flapper repair may be the solution. If water from the tank leaks around the flapper and into the toilet bowl, you likely have a leaky flapper. You can test it by pushing down on it. You should hear the water running. If the water runs but stops, the flapper isn’t sealing properly.

To replace the flapper, take the old one to a hardware store or home center and buy the one that fits your toilet. Universal flappers aren’t 100% universal. Shut off the water supply valve under the toilet. Flush the toilet to rid water from the tank, then unhook the old flapper from the mounts. Install a new flapper according to the package directions. Make sure to hook the flapper chain onto the flush lever arm so there’s a little slack when the flapper is closed. Flush a few times to make sure the chain is the right length for the new flapper.

When it comes to toilet repair, flush valve replacement may also be necessary when replacing the flapper. If a toilet flapper that is in good shape doesn’t seal, a toilet flush valve replacement may be the solution. 

Not having enough water in the tank will cause the toilet to run. Check to see if the water in the tank is at the water line. If it’s not at the line, check to make sure your water valve is on all the way.

Check the fill tube. This is a small flexible tube that runs from the fill valve to the overflow tube. If this tube falls off or if water misses the overflow tube entirely, the bowl won't fill properly. Re-attach the fill tube so that it is about one inch above the rim of the overflow tube. Flush the toilet and make sure the water goes down into the overflow tube.

Adjust the float. The water level in the tank is controlled by an adjustable float. If the float is too low, you will get a weak flush; if it’s too high, water spills into the overflow tube and the fill valve won’t shut off. Look for the fill level mark on the inside back of the tank. Flush the toilet and see if the water reaches and stops at that mark. If it doesn’t, adjust the float up or down and flush the toilet after each adjustment until it is where it needs to be.

If your fill valve won’t shut off, it’s probably faulty. If so, turn the water supply off at the shutoff under the tank and replace the valve. You can find these valves at hardware stores and home centers.

You can always count on iSky for all aspects of bathroom plumbing, including repair, replacement and installation.

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