Why Is My Toilet Slow to Fill?

Is your toilet tank filling more slowly than usual? This is a frequent toilet problem with numerous possible causes. Fortunately, none of them are major concerns or expensive to fix. Follow this guide to get your slow toilet working properly again.

How to Repair a Slow-Filling Toilet

Finding out why your toilet is slow to refill is step #1 for fixing it. Consider these potential reasons and the best way to handle each one.

Partially Closed Water Supply Valve

Look behind the toilet for the water supply hook-up connected to the wall. You’ll notice a valve connecting to it, which enables you to close off the water when your toilet is being repaired or replaced. Make sure this value is open by turning it to the left.

Issues with the Fill Valve or Tube

The fill valve, which you’ll find close to the top of a vertical tube-shaped part in the toilet tank, controls the flow of water into the tank. A toilet fill valve could degrade, clog or reposition out of alignment after years of use, stopping the tank from filling properly. Follow these tips to adjust, unclog or fix the fill valve:

  • Locate the fill valve: Open the toilet tank lid and find the fill valve inside. It’s usually installed on the left side with a tailpiece extending through the bottom of the tank and linking to the supply tube and shut-off valve.
  • Adjust the fill valve: Be certain the fill valve is secure and evenly fastened to the tube. Adjust the fill valve height if necessary by turning the adjustment knob (typical to newer toilets) or find a flathead screwdriver and loosen the adjustment screw (required for older toilets). Next, ensure that the water level is roughly one inch below the top of the overflow tube.
  • Wash the fill valve: To eliminate mineral accumulation and other sludge from the valve, first shut off the water behind the toilet and remove the fill cap. After that, slowly turn the water back on, cupping your hand over the valve to prevent from being sprayed by the water. Allow the water to flow for a few seconds to flush out dirt. Next, scrub away mineral buildup on the fill cap. If you notice cracks or significant wear and tear, replace the valve.
  • Clean the valve tube: Dirt trapped in the valve tube could also be the culprit. Shut off the water supply and take out the valve hardware. Afterward, run a thin wire or bottle brush down the tube. Turn back on the water supply slightly to rinse away the leftover residue. Re-install the valve hardware and see if the toilet fills properly.

Waterlogged Float Ball

The float ball in older toilet models rises with the water level, shutting the fill valve whenever the tank is full. If the float ball is filled with water, it blocks the tank from filling correctly.

Take off the tank lid and look inside. A partially submerged float ball may be waterlogged. Prior to replacing the ball, look at the float arm it’s attached to. If the arm is directed too low in the tank, bend it up a little bit to raise the ball’s height.

If that does not do the trick, then it might be time to just replace the component entirely. Just remember that this is old toilet technology, so it might possibly be better to modernize the existing tank components or replace the toilet completely.

Clogged Plumbing Vent

Your home plumbing system includes vents that permit air to enter the pipes. If they become clogged, tension may build within the pipes, blocking the water from flowing. This can, in turn, make your toilet fill slowly or even cause the bowl to flood.

You'll need to jump up on the roof to check for clogged plumbing vents. Look for long, vertical PVC pipes poking up from the tiles. Get rid of any animal nests, deep snow or other obstructions you find to help your plumbing work as intended.

Leaky or Blocked Pipe

If nothing is wrong with the water supply valve, fill valve and tube, float ball or plumbing vents, the slow toilet issue could stem from your supply pipes. A water line leak could prevent your toilet tank from filling correctly. It’s best to hire a licensed plumber to tackle these issues.

Schedule Toilet Repair with Midland Air Service Experts

If these tips did not handle your issue, look to Midland Air Service Experts for reliable toilet repair in Columbia. We can pinpoint the reason why your toilet is slow to fill and perform a cost-effective repair. If the fixture has hit the end of its average life span, our team can recommend high-efficiency toilet replacement in Columbia. We’ll help you find the replacement model and install it for you. Rest assured that every job we complete is supported by a 100% satisfaction guarantee! To schedule a visit from us, please contact Midland Air Service Experts today.

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