Why Is My Toilet Slow to Fill?

You flushed and now you have to wait; sound familiar? This is a common toilet problem with numerous possible causes. Thankfully, none of them are major concerns or costly to correct. Follow this guide to get your slow toilet flowing quickly again. 

How to Address a Slow-Filling Toilet 

Learning why your toilet is slow to refill is your first step toward fixing it. Keep in mind these potential reasons and the best way to handle each one. 

Partially Closed Water Supply Valve 

Look behind the toilet for the water supply hook-up attached to the wall. You’ll see a valve connecting 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 flow of water into the tank. A toilet fill valve might wear out, clog or slip out of alignment after years of use, preventing the tank from filling properly. Follow these tips to adjust, unclog or fix the fill valve: 

  • Locate the fill valve: Remove the toilet tank lid and find the fill valve inside. It’s usually installed 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: Be sure that the fill valve is secure and evenly attached to the tube. Modify the fill valve height if needed by twisting the adjustment knob (found in newer toilets) or use a flathead screwdriver to loosen and adjust (required for older toilets). Next, check that the water level is about one inch below the top of the overflow tube. 
  • Clear debris from the fill valve: To remove mineral accumulation and other dirt from the valve, first shut off the water behind the toilet and remove 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 15-20 seconds to flush out the buildup. Next, scrub away mineral buildup on the fill cap. If you observe cracks or excessive wear and tear, replace the valve. 
  • Clean the valve tube: Debris inside the valve tube could also be to blame. Shut off the water supply and remove the valve hardware. Then, run a slim wire or bottle brush into the tube. Open the water supply slightly to flush away the leftover residue. Reconnect the valve hardware and verify if the toilet fills properly. 

Waterlogged Float Ball 

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

Pull up the tank lid and peek inside. A partially submerged float ball may be waterlogged. Before running out to buy a new ball, examine the float arm it’s connected to. If the arm is directed too low in the tank, bend it up a little bit to raise the ball’s height. 

If that does not do the trick, you may be able to install a new float ball. Just be aware that this is old toilet technology, so it may be better to update the existing tank components or change out the toilet entirely. 

Plugged Plumbing Vent 

Your home plumbing system uses vents that allow air to enter the pipes. If they end up being 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 flood. 

You should grab a ladder and climb up on the roof to search for clogged plumbing vents. Look for long, vertical PVC pipes poking up from the shingles. Clear away any animal nests, deep snow or other obstructions you see to help your plumbing work 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 problem could stem from your supply pipes. A problem with the water line itself could stop your toilet tank from filling correctly. It’s a good idea to hire a licensed plumber to tackle 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 dependable toilet repair in the U.S.. We can identify the reason why this is happening and perform the most appropriate repair. If the fixture has hit the end of its average life span, our company can propose high-efficiency toilet replacement in the U.S.. We’ll help you pick out the replacement model and install it on your behalf. You can relax knowing that every job we execute is supported by a 100% satisfaction guarantee! To schedule a visit from us, please connect with Service Experts Heating, Air Conditioning & Plumbing today. 

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