Why Is My Toilet Slow to Fill?

You flushed and now you have to wait; sound familiar? This is a frequent toilet predicament with multiple possible reasons. Fortunately, none of them are serious concerns or costly to correct. Follow this guide to get your slow toilet functioning properly again. 

How to Address a Slow-Filling Toilet 

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

Partially Closed Water Supply Valve 

Take a peek behind the toilet for the water supply hose attached to the wall. You’ll find a valve attached to it, which allows you to close off the water during toilet repairs and replacements. Check this valve to make sure it’s completely open. 

Issues with the Fill Valve or Tube 

The fill valve, which is close to the top of a vertical tube-shaped part in the toilet tank, regulates the flow of water into the tank. A toilet fill valve may break down, clog or move out of alignment after years of use, stopping the tank from filling properly. Follow these tips to adjust, clean or fix the fill valve: 

  • Search for the fill valve: Open the toilet tank lid and find the fill valve inside. It’s commonly 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: Make sure the fill valve is secure and evenly fastened to the tube. Change the fill valve height if required by turning the adjustment knob (common to newer toilets) or loosening the adjustment screw with a flathead screwdriver (required for older toilets). After that, check that 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 sludge from the valve, first shut off the water behind the toilet and take off the fill cap. Right after that, slowly turn the water back on, cupping your hand over the valve to keep from being sprayed. Allow the water to flow for a few seconds to flush out dirt. Next, scrub away mineral buildup from the fill cap. If you detect cracks or significant wear and tear, replace the valve. 
  • Clean the valve tube: Dirt lodged in the valve tube could also be at fault. Shut off the water supply and take off the valve hardware. Then, run a slim wire or bottle brush into the tube. Start the water supply slightly to flush away the remaining residue. Replace the valve hardware and see 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 is damaged or punctured and fills with water, it blocks the tank from filling correctly. 

Pull up the tank lid and view 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 lift 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 be aware that this is an older toilet design, so it may well be better to upgrade the existing tank components or replace the toilet entirely. 

Plugged Plumbing Vent 

Your home plumbing system includes vents that allow air to enter the pipes. If they become clogged, stress may build within the pipes, blocking the water from flowing. This can, in turn, make your toilet fill slowly or even cause the bowl to overflow. 

You should grab a ladder and climb up on the roof to look 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 find 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 issue could stem from your supply pipes. A problem with the water line itself could stop your toilet tank from filling properly. It’s safest to hire a licensed plumber to fix 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 quality toilet repair in the U.S.. We can figure out the reason why the water flow is so slow and perform a budget-friendly repair. If the fixture has hit the end of its useful life span, our team can suggest high-efficiency toilet replacement in the U.S.. We’ll help you find the replacement model and install it for you. Rest assured that every job we perform 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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