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 predicament with multiple possible reasons. Luckily, none of them are serious concerns or costly to fix. Follow this guide to get your slow toilet functioning efficiently again. 

How to Address a Slow-Filling Toilet 

Finding out why your toilet is slow to fill is step #1 for fixing it. Think about these possible reasons and the best way to handle each one. 

Partially Closed Water Supply Valve 

Look behind the toilet for the water supply hose connected to the wall. You’ll see a valve attached to it, which allows you to shut off the water when repairs or full replacement of the tank is needed. Check this valve to make sure it’s completely open. 

Trouble with the Fill Valve or Tube 

The fill valve, which you’ll find attached to the top of a vertical tube device in the toilet tank, regulates the water flow into the tank. A toilet fill valve may break down, clog or shift out of alignment after years of use, hindering the tank from filling properly. Follow these instructions to adjust, unclog or fix the fill valve: 

  • Find the fill valve: Lift the toilet tank lid and find the fill valve inside. It’s normally 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 certain the fill valve is secure and evenly fastened to the tube. Alter the fill valve height if needed by twisting the adjustment knob (found in newer toilets) or loosening the adjustment screw with a flathead screwdriver (required for older toilets). Then, ensure that the water level is approximately one inch below the top of the overflow tube. 
  • Clean the fill valve: To remove mineral buildup and other gunk from the valve, first shut off the water in the rear of the toilet and take off the fill cap. After that, slowly turn the water back on, cupping your hand over the valve to keep from being sprayed. Let the water flow for several seconds to flush out debris. Next, scrub away mineral buildup from the fill cap. If you detect cracks or substantial wear and tear, replace the valve. 
  • Clean the valve tube: Debris lodged in the valve tube could also be the culprit. Shut off the water supply and take off the valve hardware. Afterward, run a slim wire or bottle brush down the tube. Start the water supply slightly to clean away the remaining residue. Replace the valve hardware and check if the toilet fills properly. 

Waterlogged Float Ball 

The float ball in older toilet models rises with the water level, shutting the fill valve once the tank is full. If the float ball is filled with water, it prevents the tank from filling efficiently. 

Remove the tank lid and look inside. A partially submerged float ball could be waterlogged. Before running out to buy a new ball, check the float arm it’s attached to. If the arm is pointed too low in the tank, bend it up a little bit to elevate the ball’s height. 

If this doesn’t work, then it might be time to just replace the component entirely. Just be aware that this is old toilet technology, so it might possibly be better to upgrade the existing tank components or switch out the toilet entirely. 

Clogged Plumbing Vent 

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

You need to get on the roof to look for clogged plumbing vents. Search for long, vertical PVC pipes poking up from the shingles. Clear away any animal nests, deep snow or other obstructions you see to guarantee that your plumbing can function 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 dilemma could stem from your supply pipes. A leak or blockage in the water line could prevent your toilet tank from filling appropriately. It’s best to hire a licensed plumber to fix 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 reliable toilet repair in the U.S.. We can figure out 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 company can recommend high-efficiency toilet replacement in the U.S.. We’ll help you decide on the replacement model and install it for you. Rest assured that every job we perform is backed by a 100% satisfaction guarantee! To schedule a visit from us, please contact Service Experts Heating, Air Conditioning & Plumbing today. 

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