Why Is My Toilet Slow to Fill?

You flushed and now you have to wait; sound familiar? This is a frequent toilet predicament with numerous possible causes. Thankfully, none of them are serious concerns or costly to address. Follow this guide to get your slow toilet flowing efficiently again. 

How to Address a Slow-Filling Toilet 

Understanding why your toilet is slow to refill is step #1 for fixing it. Think about these potential reasons and how to deal with each one. 

Partially Closed Water Supply Valve 

Look behind the toilet for the water supply line connected to the wall. You’ll find a valve connecting to it, which helps you to shut off the water when repairs or full replacement of the tank is needed. Make sure this value is open by turning it to the left. 

Problems 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, manages the flow of water into the tank. A toilet fill valve might degrade, clog or reposition out of alignment after years of use, preventing the tank from filling appropriately. Follow these tips to adjust, clear out or fix the fill valve: 

  • Locate the fill valve: Lift the toilet tank lid and find the fill valve inside. It’s usually mounted on the left side with a tailpiece extending through the bottom of the tank and connecting to the supply tube and shut-off valve. 
  • Adjust the fill valve: Check that the fill valve is secure and evenly connected to the tube. Change the fill valve height if needed by twisting the adjustment knob (typical to newer toilets) or find a flathead screwdriver and loosen the adjustment screw (required for older toilets). After that, make sure the water level is about one inch below the top of the overflow tube. 
  • Clear debris from the fill valve: To get rid of mineral accumulation and other debris 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 a few 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 to blame. Turn off the water supply and remove the valve hardware. Afterward, run a slim wire or bottle brush down the tube. Start the water supply slightly to rinse away the excess residue. Re-install the valve hardware and confirm if the toilet fills quicker. 

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 is filled with water, it blocks the tank from filling properly. 

Pull up the tank lid and peek inside. A partially submerged float ball might be waterlogged. Before you replace the ball, look at the float arm it’s attached to. If the arm is directed too low in the tank, bend it up slightly to elevate the ball’s height. 

If that does not do the trick, 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 old toilet technology, so it might possibly be better to upgrade the existing tank components or change out the toilet entirely. 

Blocked Plumbing Vent 

Your home plumbing system features vents that permit air to enter the pipes. If they end up being clogged, pressure 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 look for clogged plumbing vents. Start looking for long, vertical PVC pipes poking up from the tiles. 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 there’s nothing apparently 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 leak or blockage in the water line could stop your toilet tank from filling appropriately. It’s a good idea to hire a licensed plumber to fix these issues. 

Schedule Toilet Repair with Mid-State Air Conditioning, Heating & Plumbing 

When all else fails, turn to Mid-State Air Conditioning, Heating & Plumbing for dependable toilet repair in Nashville. We can identify the reason why the water flow is so slow and perform a cost-effective repair. If the fixture has hit the end of its useful life span, our team can suggest high-efficiency toilet replacement in Nashville. We’ll help you find 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 contact Mid-State Air Conditioning, Heating & Plumbing today. 

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