Why Is My Toilet Slow to Fill?

You flushed and now you have to wait; sound familiar? This is a frequent toilet problem with numerous possible causes. Thankfully, none of them are major concerns or expensive to address. Follow this guide to get your slow toilet working properly again. 

How to Fix a Slow-Filling Toilet 

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

Partially Closed Water Supply Valve 

Look behind the toilet for the water supply line attached to the wall. You’ll see a valve connecting to it, which allows you to close off the water during toilet repairs and replacements. Make sure this value is open by turning it to the left. 

Problems with the Fill Valve or Tube 

The fill valve, which can be found close to the top of a vertical tube device in the toilet tank, controls 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, unclog or fix the fill valve: 

  • Search for the fill valve: Lift 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: Be sure that the fill valve is secure and evenly attached to the tube. Alter the fill valve height if necessary by twisting the adjustment knob (typical to newer toilets) or loosening the adjustment screw with a flathead screwdriver (required for older toilets). Next, check that the water level is roughly one inch below the top of the overflow tube. 
  • Wash the fill valve: To take out mineral buildup and other debris 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 avoid getting sprayed. Let the water flow for several seconds to flush out dirt. Next, scrub away mineral buildup on the fill cap. If you observe 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 take out the valve hardware. Next, run a slim wire or bottle brush down the tube. Open the water supply slightly to rinse away the leftover residue. Re-install the valve hardware and check if the toilet fills faster now. 

Waterlogged Float Ball 

The float ball in older toilet models rises with the water level, shutting the fill valve when the tank has filled. If the float ball is damaged or punctured and fills with water, it blocks the tank from filling properly. 

Pull up the tank lid and view inside. A partially submerged float ball might be waterlogged. Before running out to buy a new ball, check the float arm it’s secured to. If the arm is fixed too low in the tank, bend it up a little bit to elevate the ball’s height. 

If this doesn’t work, 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 modernize the existing tank components or change out the toilet completely. 

Blocked Plumbing Vent 

Your home plumbing system uses vents that enable air to enter the pipes. If they end up clogged, stress may build inside of the pipes, blocking the water from flowing. This can, in turn, make your toilet slow to fill or even cause the bowl to flood. 

You’ll need to jump up on the roof to check for clogged plumbing vents. Search for long, vertical PVC pipes poking up from the roof tiles. Do away with any animal nests, deep snow or other obstructions you see 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 dilemma could stem from your supply pipes. A problem with the water line itself could stop your toilet tank from filling properly. It’s a good idea to hire a licensed plumber to tackle these issues. 

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

If these tips did not handle your issue, look to Service Experts Heating, Air Conditioning & Plumbing for dependable toilet repair in the U.S.. We can pinpoint the reason why the water flow is so slow and perform a cost-effective 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 pick out the replacement model and install it on your behalf. Relax knowing that every job we perform is protected by a 100% satisfaction guarantee! To schedule a visit from us, please contact Service Experts Heating, Air Conditioning & Plumbing today. 

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