How to Fix a Toilet Fill Valve

Two things need to happen in order for a toilet (the ones we have today) to work: there must be sufficient water in the water tank to successfully flush and tank water should discharge into the bowl with just the right amount of force to flush the waste from the bowl.

This means that the water in the tank shouldn’t be too high or too low – it needs to be just right. Too much water leads to water running through the overflow tube and into the bowl. Too little water coupled with less pressure results in waste not being sent to the sewer system.

A valve located on the lower right side of the toilet tank is how water enters the tank. Water then moves up a flexible pipe then goes into a fill valve located inside the toilet.

There are two kinds of valves available: an old-style fill valve and a new-style fill valve which is cylindrical in shape. When you run into a problem, most likely, you’ll need to adjust the water level in the tanks using the valve.

The great thing about a fill valve is that you can do it all by yourself. Yes, it’s understandable that you might want to hire a professional to do this just to be sure. But if you want to save on money and time, you can always embrace the DIY method.

Fixing an Old-Style Fill Valve

This kind of fill tube uses a plastic buoyant ball that is screwed on a thread rod which lowers when the toilet is flushed. This results in the valve opening to allow the tank to refill water.

When water fills the tank, the ball will rise with the water level then closes the fill valve which then shuts the water off. A screw located on top of the fill valve is used to adjust the valve’s movement. In order to reduce the amount of water level in the tank, simply turn the screw clockwise.

To know the proper water level for the tank, check the line on the overflow tube. You can keep adjusting the screw until the water hits the line. Also, make sure that you don’t bend the rod. After a short while, the ball will be in the opposite direction you intended because of water pressure in the tank.

Fixing a New-Style Fill Valve

Fill valves of this kind look like a plastic cylinder with that cylinder being a float which is adjustable so the water level can be controlled. Being of the new style, different manufacturers employ their own design. As such, each fill valve differs in how the cylinder is released. So, in order to fix this kind of valve, you must know the maker of the valve then go their website to find out how to adjust their valve.

Sometimes, Newer Is Better

Many would suggest a move from the rod-and-ball kind of fill valve to the more cylindrical model. And that’s not a wrong thing to do as well. Why is that? The rod-and-ball model is old and the newer designs are easier to replace. You don’t even have to do a lot to replace the new models, you just

  • Shut off the water to the tank.
  • Unscrew the nut that is attached to the fill valve.
  • Remove the old valve then replace it with the new one.

Not so bad, right? And the part doesn’t cost much – around $10 to $20. Plus, replacing it won’t take an hour to do.

Knowing When a Fill Valve Needs To Be Replaced

Fill valves will wear out but rather than wait for it to deteriorate completely, it’s best to recognize signs of trouble so you can take action before the problem gets worse. Here are some of the common signs that a fill valve needs replacing:

It Hums And Screams

This is particularly true with old ballcock-style fill valves when they wear out. When this happens, the valve won’t open or close as smoothly as it once did. As such, the force of water that flows through it will create a certain sound effect that is not pleasant to the ears.

You may notice a low, humming sound that you’re willing to disregard as it is almost inaudible. However, doing so just leads to greater trouble. Hearing sounds is a good sign that something is not right with your toilet. The sounds you hear is water not being able to flow freely. Not attending to these results in louder sounds that seem like screaming. When this happens, the metal parts are already loose and not doing something will lead to the valve failing. In cases like this, repairing it is pointless; you need to get a replacement and as mentioned earlier, replacements aren’t expensive.

A Running Toilet

When the flapper is leaking, the tank slowly drains and causes the fill valve to run all the time. Then again, the toilet will also run if the fill valve is worn out. But if you want to make sure the flapper is not the cause of the issue, do the following:

  • Put dye into the toilet tank.
  • Wait for a couple of hours before checking the toilet again.
  • When the water in the bowl doesn’t change color, the fault is with the fill valve.

As mentioned in this post, the valve is responsible for the water level in the tank. So rather than chuck the valve out, you can just simply adjust it.

Other Fill Valve Replacement Tips

A float that is not adjusted right is one of the most common reasons for a fill valve that doesn’t turn off completely. Try adjusting the rod length on a cup float or adjust the valve tension using a screwdriver first before unscrewing the ball in order to lengthen the float arm. In case the water doesn’t shut off or you still hear sounds, the valve definitely needs to be replaced. Also, if you can’t find the right float and valve adjustments so the water turns off completely, it’s always best to replace the fill valve.

Today, you can find universal fill valves at your local hardware store. These don’t have metal parts so there’s less chance of corroding which means that it will most likely last as long as the life of your toilet.

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