Why Is My Toilet Slow to Fill?

You flushed and now you have to wait; sound familiar? This is a known toilet problem with multiple possible culprits. Fortunately, none of them are serious concerns or costly to deal with. Follow this guide to get your slow toilet working quickly again. 

How to Repair a Slow-Filling Toilet 

Finding out why your toilet is slow to fill is your first step toward fixing it. Consider these potential reasons and how to deal with each one. 

Partially Closed Water Supply Valve 

Check behind the toilet for the water supply line connected to the wall. You’ll notice a valve connecting to it, which enables you to shut off the water when your toilet is being repaired or replaced. Check this valve to make sure it’s completely open. 

Problems with the Fill Valve or Tube 

The fill valve, which you’ll find connected to the top of a vertical tube-shaped part in the toilet tank, regulates the water flow into the tank. A toilet fill valve may break down, clog or reposition out of alignment after years of use, preventing the tank from filling appropriately. Follow these instructions to adjust, unclog or fix the fill valve: 

  • Search for the fill valve: Remove the toilet tank lid and find the fill valve inside. It’s normally installed on the left side with a tailpiece extending through the bottom of the tank and connecting to the supply tube and shut-off valve. 
  • Adjust the fill valve: Be certain the fill valve is secure and evenly attached to the tube. Alter the fill valve height if required by turning the adjustment knob (common to newer toilets) or loosening the adjustment screw with a flathead screwdriver (required for older toilets). After that, ensure that the water level is about one inch below the top of the overflow tube. 
  • Clean the fill valve: To get rid of mineral buildup and other gunk from the valve, first shut off the water in the rear of 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. Let the water flow for several seconds to flush out dirt. Next, scrub away mineral buildup off the fill cap. If you notice cracks or excessive wear and tear, replace the valve. 
  • Clean the valve tube: Dirt trapped in the valve tube could also be to blame. Turn off the water supply and take out the valve hardware. Afterward, run a slim wire or bottle brush down the tube. Turn back on the water supply slightly to rinse away the remaining residue. Replace the valve hardware and confirm if the toilet fills properly. 

Waterlogged Float Ball 

The float ball in older toilet models rises with the water level, closing the fill valve when the tank is full. If the float ball takes on water, it prevents the tank from filling efficiently. 

Pull up the tank lid and peek inside. A partially sunken float ball may be waterlogged. Before you replace the ball, check the float arm it’s secured to. If the arm is fixed too low in the tank, bend it up slightly to lift the ball’s height. 

If that fails to solve the issue, you may be able to install a new float ball. But it’s worth remembering that this is old toilet technology, so it may be better to modernize the existing tank parts or replace the toilet completely. 

Blocked Plumbing Vent 

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

You should grab a ladder and climb up on the roof to search for clogged plumbing vents. Look for long, vertical PVC pipes poking up from the roof tiles. Clear away 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 problem could stem from your supply pipes. A problem with the water line itself could prevent your toilet tank from filling correctly. It’s a good idea to hire a licensed plumber to tackle these issues. 

Schedule Toilet Repair with Stevenson Service Experts 

If these tips did not handle your issue, look to Stevenson Service Experts for dependable toilet repair in Columbus. We can figure out the reason why your toilet is slow to fill and perform a budget-friendly repair. If the fixture has reached the end of its useful life span, our company can propose high-efficiency toilet replacement in Columbus. We’ll help you decide on the replacement model and install it on your behalf. Rest assured that every job we complete is supported by a 100% satisfaction guarantee! To schedule a visit from us, please connect with Stevenson Service Experts today. 

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