Why Is My Toilet Slow to Fill?

Have you noticed that your toilet is taking longer to refill after flushing? This is a frequent toilet issue with several possible culprits. Luckily, none of them are major concerns or costly to correct. Follow this guide to get your slow toilet functioning quickly again. 

How to Repair a Slow-Filling Toilet 

Learning why your toilet is slow to refill is step #1 for fixing it. Keep in mind these possible reasons and how to handle each one. 

Partially Closed Water Supply Valve 

Take a peek behind the toilet for the water supply hook-up connected to the wall. You’ll see a valve attached to it, which helps you to turn off the water when your toilet is being repaired or replaced. Check this valve to make sure it’s completely open. 

Trouble with the Fill Valve or Tube 

The fill valve, which can be found attached to the top of a vertical tube device in the toilet tank, controls the water flow into the tank. A toilet fill valve may wear out, clog or shift out of alignment after years of use, stopping the tank from filling appropriately. Follow these tips to adjust, clear out or fix the fill valve: 

  • Find the fill valve: Open the toilet tank lid and find the fill valve inside. It’s usually 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: Make sure the fill valve is secure and evenly attached to the tube. Modify the fill valve height if needed by turning the adjustment knob (found in newer toilets) or find a flathead screwdriver and loosen the adjustment screw (required for older toilets). After that, check that the water level is about one inch below the top of the overflow tube. 
  • Wash the fill valve: To remove mineral accumulation and other gunk from the valve, first shut off the water in the back of the toilet and take off 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. Let the water flow for several seconds to flush out debris. Next, scrub away mineral buildup off 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 at fault. Shut off the water supply and remove the valve hardware. Then, run a thin wire or bottle brush into the tube. Turn back on the water supply slightly to flush away the leftover residue. Replace 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, closing the fill valve whenever the tank has filled. If the float ball takes on water, it prevents the tank from filling properly. 

Take off the tank lid and peek inside. A partially sunken float ball could be waterlogged. Before you replace the ball, examine the float arm it’s secured to. If the arm is pointed too low in the tank, bend it up somewhat to raise the ball’s height. 

If this doesn’t work, you may be able to install a new float ball. Just remember that this is old toilet technology, so it might possibly be better to upgrade the existing tank parts or switch out the toilet altogether. 

Clogged Plumbing Vent 

Your home plumbing system features vents that allow air to enter the pipes. If they become clogged, tension may build throughout the pipes, preventing the water from flowing. This can, in turn, make your toilet fill at a snail’s pace or even cause the bowl to overrun. 

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 roof tiles. Clear away any animal nests, deep snow or other obstructions you notice to guarantee that your plumbing can function 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 issue could stem from your supply pipes. A problem with the water line itself could prevent 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 

When all else fails, turn to Service Experts Heating, Air Conditioning & Plumbing for reliable toilet repair in the U.S.. We can pinpoint the reason why the water flow is so slow and perform the most appropriate repair. If the fixture has hit the end of its typical life span, our specialists can suggest high-efficiency toilet replacement in the U.S.. We’ll help you decide on the replacement model and install it for you. You can relax knowing that every job we perform is supported by a 100% satisfaction guarantee! To schedule a visit from us, please contact Service Experts Heating, Air Conditioning & Plumbing today. 

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