Why Is My Toilet Slow to Fill?

Have you noticed that your toilet is taking longer to refill after flushing? This is a known toilet problem with multiple possible culprits. Luckily, none of them are serious concerns or costly to address. Follow this guide to get your slow toilet functioning efficiently again. 

How to Repair a Slow-Filling Toilet 

Understanding why your toilet is slow to refill is step #1 for 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 find a valve attached to it, which helps you to shut off the water during toilet repairs and replacements. Examine the value to ensure it is fully open. 

Problems with the Fill Valve or Tube 

The fill valve, which is connected to the top of a vertical tube-shaped part in the toilet tank, controls the water flow into the tank. A toilet fill valve may wear out, clog or slip out of alignment after years of use, hindering the tank from filling properly. Follow these tips to adjust, clean or fix the fill valve: 

  • Search for the fill valve: Lift the toilet tank lid and find the fill valve inside. It’s commonly secured 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 sure that the fill valve is secure and evenly connected to the tube. Adjust the fill valve height if needed by turning the adjustment knob (common to newer toilets) or use a flathead screwdriver to loosen and adjust (required for older toilets). After that, check that the water level is approximately one inch below the top of the overflow tube. 
  • Clean the fill valve: To take out 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 a few 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 lodged in the valve tube could also be to blame. Shut off the water supply and take out the valve hardware. Afterward, run a thin wire or bottle brush into the tube. Open the water supply slightly to rinse away the leftover residue. Re-install the valve hardware and verify if the toilet fills faster now. 

Waterlogged Float Ball 

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

Remove the tank lid and view inside. A partially sunken float ball may be waterlogged. Before you replace the ball, check the float arm it’s attached to. If the arm is pointed too low in the tank, bend it up somewhat to raise the ball’s height. 

If that does not do the trick, then it might be time to just replace the component entirely. But it’s worth remembering that this is old toilet technology, so it might possibly be better to modernize the existing tank components or change out the toilet entirely. 

Blocked Plumbing Vent 

Your home plumbing system includes vents that allow air to enter the pipes. If they are clogged, stress may build within the pipes, stopping the water from flowing. This can, in turn, make your toilet fill at a snail’s pace or even cause the bowl to flood. 

You’ll need to jump up on the roof to search for clogged plumbing vents. Look for long, vertical PVC pipes poking up from the shingles. Do away with any animal nests, deep snow or other obstructions you find to ensure your plumbing works properly. 

Leaky or Blocked Pipe 

If you can’t find anything wrong with the water supply valve, fill valve and tube, float ball or plumbing vents, the slow toilet dilemma could stem from your supply pipes. A problem with the water line itself could prevent your toilet tank from filling correctly. It’s best to hire a licensed plumber to tackle these issues. 

Schedule Toilet Repair with Service Experts Heating, Air Conditioning & Plumbing 

If these tips did not handle your issue, look to Service Experts Heating, Air Conditioning & Plumbing for quality toilet repair in the U.S.. We can identify the reason why the water flow is so slow and perform a budget-friendly repair. If the fixture has hit the end of its typical life span, our team can suggest high-efficiency toilet replacement in the U.S.. We’ll help you decide on the replacement model and install it for you. Relax knowing that every job we execute is supported by a 100% satisfaction guarantee! To schedule a visit from us, please connect with Service Experts Heating, Air Conditioning & Plumbing today. 

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