A toilet tank that won't fill with water at all is an uncommon problem, but it's a frustrating one. Thankfully, it's usually easy to fix. Water comes through the supply valve at the wall, runs through the supply line, and then enters the tank through the fill valve. In order to fix the problem, you'll need to inspect all these components in order. To find out how, follow the guide below.

1. Check Supply Valve

The first step is to check if the water supply to the toilet has accidentally been turned off. Locate the supply valve underneath the toilet and turn it counter-clockwise to open it. If it was closed, the toilet tank should start filling with water within a few seconds.

If the supply valve was already open, turn it clockwise to close it. The water supply to the toilet needs to be shut off for the next two steps.

2. Check Supply Line

The supply line leads from the supply valve to the toilet tank, and it can sometimes become clogged with debris. Double-check to make sure that the supply valve is turned clockwise, and then unscrew the supply line from the tank with your hand.

Take a flashlight and inspect the supply line for obstructions. If you notice one, try to carefully remove it with a straightened wire hanger. If you can't remove the obstruction or if the supply line is kinked too badly to let water through, you'll need to replace it.

You can buy toilet supply lines at any home improvement store, and they're easy to replace. All you need to do is to remove the old supply line from the supply valve using a wrench, then connect the new supply line to the valve and the toilet tank.

3. Check Fill Valve

The supply line connects to the fill valve in the toilet, which can also become obstructed. If your supply line looked fine, you'll need to check the fill valve.

Double-check to make sure the water supply to the toilet is shut off, and then take the lid off of your toilet tank. The fill valve is the pipe that has an arm attached to the top of it. You'll need to remove the cap on top of the fill valve. Hold the valve steady with one hand while turning the cap in order to remove it.

The purpose of the cap is to slow down the rate of water entering into the tank, so removing it allows you to attempt to blast away any obstructions in the fill valve with a forceful flow of water. Place a plastic cup over the fill valve at an angle to prevent water from spraying all over your bathroom, and then open the supply valve.

If no water comes out of the fill valve with the supply valve open, close the supply valve again. Use your flashlight to inspect the fill valve for any large obstructions you may be able to fish out with a wire hanger. If you can see straight down to the supply line, it's time to call a plumber.

After completing all of these steps, you've checked everything from the wall to the toilet tank. If your toilet tank still isn't filling with water, it means that the problem lies upstream of your toilet within your home's plumbing system. In order to fix your problem, you'll need to call a plumbing repair service, such as Edelman Inc, to have your supply pipes inspected.