Troubleshooting a Toilet Tank That Fills Slowly

An open toilet against a green wall.

A slow filling toilet tank can be very frustrating, but luckily, it is usually fixed very easily. Here are some tips for troubleshooting your toilet tank when this problem occurs.

Partially Open Valve

A toilet in a bathroom.

A common problem with slow filling toilets usually comes from the water supply valve underneath the tank. If it is partially open, make sure you open it entirely so water can flow as freely as possible into the tank.

Tube Clogs

A toilet in a bathroom.

Another issue that causes the toilet tank to fill too slowly is a clog in the valve tube. To fix this problem, turn the valve by the wall to shut off the water. Then, take the hardware off the valve and use a bottle brush or wire to unclog the tube. Placing a cup over the tube, open and shut the valve a few times to make sure the tube is completely flushed. Then, secure the hardware over the valve.

Low Water Pressure

A toilet in a bathroom with a brick wall.

One other possible reason a toilet tank may be filling slowly is because of low water pressure. In this case, installing a booster tank should help bring up the water pressure. Pressure can be increased for well water by turning it up at the well tank, though a new tank or pump may be necessary.

With these troubleshooting tips, fixing your slow filling toilet tank should be a breeze. Time to move on to problem number two.