Why Is My Toilet Slow to Fill?

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

How to Repair a Slow-Filling Toilet 

Finding out why your toilet is slow to refill is step #1 for fixing it. Think about these potential reasons and how to handle each one. 

Partially Closed Water Supply Valve 

Take a peek behind the toilet for the water supply line attached to the wall. You’ll notice a valve attached to it, which helps you to turn off the water when repairs or full replacement of the tank is needed. Examine the value to ensure it is fully open. 

Issues with the Fill Valve or Tube 

The fill valve, which is attached to the top of a vertical tube-shaped part in the toilet tank, regulates the water flow into the tank. A toilet fill valve might wear out, 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: 

  • Locate the fill valve: Remove 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 attaching to the supply tube and shut-off valve. 
  • Adjust the fill valve: Make sure the fill valve is secure and evenly attached to the tube. Change 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, ensure 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 sludge 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 keep from being sprayed. Allow the water to 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 the culprit. Turn off the water supply and remove the valve hardware. Next, run a thin wire or bottle brush into the tube. Start the water supply slightly to clean away the leftover residue. Replace the valve hardware and see 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 has filled. If the float ball is filled with water, it keeps the tank from filling properly. 

Pull up the tank lid and look inside. A partially sunken float ball could be waterlogged. Before you replace the ball, examine the float arm it’s attached to. If the arm is directed too low in the tank, bend it up somewhat to lift the ball’s height. 

If that fails to solve the issue, you might want to simply buy a new float ball; the average cost of this product ranges between $7-$20 in most hardware or home improvement stores. Just remember that this is an older toilet design, so it might possibly be better to update the existing tank hardware or change out the toilet entirely. 

Blocked Plumbing Vent 

Your home plumbing system includes vents that enable air to enter the pipes. If they are clogged, tension may build within the pipes, stopping the water from flowing. This can, in turn, make your toilet slow to fill or even cause the bowl to overflow. 

You need to get on the roof to search for clogged plumbing vents. Start looking for long, vertical PVC pipes poking up from the shingles. Get rid of any animal nests, deep snow or other obstructions you notice to help your plumbing work as intended. 

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 problem could stem from your supply pipes. A leak or blockage in the water line could restrict your toilet tank from filling appropriately. It’s safest to hire a licensed plumber to handle these issues. 

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

Is your toilet still not working right? Turn to Service Experts Heating, Air Conditioning & Plumbing for dependable toilet repair in the U.S.. We can figure out the reason why the water flow is so slow and perform the most appropriate repair. If the fixture has come to the end of its average life span, our team can propose high-efficiency toilet replacement in the U.S.. We’ll help you pick out the replacement model and install it for you. You can relax knowing that every job we complete is backed by a 100% satisfaction guarantee! To schedule a visit from us, please call Service Experts Heating, Air Conditioning & Plumbing today. 

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