Why Is My Toilet Slow to Fill?

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

How to Fix a Slow-Filling Toilet 

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

Partially Closed Water Supply Valve 

Check behind the toilet for the water supply line attached to the wall. You’ll find a valve attached to it, which helps you to turn off the water when your toilet is being repaired or replaced. Examine the value to ensure it is fully open. 

Issues with the Fill Valve or Tube 

The fill valve, which you’ll find attached to the top of a vertical tube-shaped part in the toilet tank, controls the water level flowing into the tank. A toilet fill valve might degrade, clog or move out of alignment after years of use, preventing the tank from filling right. Follow these instructions to adjust, clear out or fix the fill valve: 

  • Find the fill valve: Remove the toilet tank lid and find the fill valve inside. It’s normally mounted on the left side with a tailpiece extending through the bottom of the tank and attaching to the supply tube and shut-off valve. 
  • Adjust the fill valve: Be sure that the fill valve is secure and evenly attached to the tube. Modify the fill valve height if needed by twisting the adjustment knob (found in newer toilets) or use a flathead screwdriver to loosen and adjust (required for older toilets). After that, verify that the water level is approximately one inch below the top of the overflow tube. 
  • Wash the fill valve: To remove mineral accumulation and other sludge from the valve, first shut off the water behind the toilet and remove the fill cap. Right 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 15-20 seconds to flush out debris. 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 inside the valve tube could also be at fault. Turn off the water supply and take off 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 leftover residue. Re-install the valve hardware and verify if the toilet fills quicker. 

Waterlogged Float Ball 

The float ball in older toilet models rises with the water level, shutting the fill valve whenever the tank has filled. If the float ball takes on water, it prevents the tank from filling correctly. 

Take off the tank lid and view inside. A partially sunken float ball may be waterlogged. Before you replace the ball, examine the float arm it’s attached to. If the arm is pointed too low in the tank, bend it up slightly 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 be aware that this is old toilet technology, so it may be better to modernize the existing tank parts or replace the toilet completely. 

Clogged Plumbing Vent 

Your home plumbing system features vents that enable air to enter the pipes. If they end up clogged, tension may build throughout the pipes, preventing the water from flowing. This can, in turn, make your toilet fill slowly or even cause the bowl to overflow. 

You’ll need to jump up on the roof to search for clogged plumbing vents. Start looking for long, vertical PVC pipes poking up from the shingles. Clear away 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 issue could stem from your supply pipes. A problem with the water line itself could stop your toilet tank from filling appropriately. It’s a good idea to hire a licensed plumber to handle these issues. 

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

When all else fails, turn to Service Experts Heating, Air Conditioning & Plumbing for quality toilet repair in the U.S.. We can pinpoint the reason why this is happening and perform a cost-effective 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 on your behalf. You can relax knowing that every job we complete is protected 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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