Why Is My Toilet Slow to Fill?

Have you noticed that your toilet is taking longer to refill after flushing? This is a known toilet predicament with multiple possible reasons. Fortunately, none of them are major concerns or expensive to deal with. Follow this guide to get your slow toilet working efficiently again. 

How to Repair a Slow-Filling Toilet 

Finding out why your toilet is slow to refill is step #1 for fixing it. Think about these potential reasons and how to handle each one. 

Partially Closed Water Supply Valve 

Check behind the toilet for the water supply hose connected to the wall. You’ll see a valve attached to it, which allows you to turn off the water when your toilet is being repaired or replaced. Check this valve to make sure it’s completely open. 

Issues with the Fill Valve or Tube 

The fill valve, which you’ll find connected to the top of a vertical tube-shaped part in the toilet tank, controls the flow of water into the tank. A toilet fill valve could break down, clog or reposition out of alignment after years of use, preventing the tank from filling properly. Follow these instructions to adjust, unclog or fix the fill valve: 

  • Locate the fill valve: Open the toilet tank lid and find the fill valve inside. It’s normally 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 certain the fill valve is secure and evenly fastened to the tube. Alter the fill valve height if necessary by turning the adjustment knob (typical to newer toilets) or use a flathead screwdriver to loosen and adjust (required for older toilets). After that, verify that the water level is roughly one inch below the top of the overflow tube. 
  • Clean the fill valve: To remove mineral accumulation and other gunk from the valve, first shut off the water in the back of 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 several seconds to flush out debris. Next, scrub away mineral buildup on the fill cap. If you detect cracks or significant wear and tear, replace the valve. 
  • Clean the valve tube: Debris trapped in the valve tube could also be to blame. Shut off the water supply and remove the valve hardware. Next, run a thin wire or bottle brush down the tube. Turn back on 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, sealing the fill valve when the tank is full. 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 sunken float ball may be waterlogged. Before running out to buy a new ball, check the float arm it’s secured 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 may be able to install a new float ball. Just be aware that this is an older toilet design, so it may well be better to update the existing tank components or change out the toilet entirely. 

Clogged Plumbing Vent 

Your home plumbing system features vents that enable air to enter the pipes. If they are clogged, stress may build throughout the pipes, blocking the water from flowing. This can, in turn, make your toilet slow to fill or even cause the bowl to overrun. 

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 tiles. Do away with any animal nests, deep snow or other obstructions you notice to ensure your plumbing works properly. 

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 problem could stem from your supply pipes. A leak or blockage in the water line could prevent your toilet tank from filling appropriately. It’s safest to hire a licensed plumber to fix 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 figure out the reason why your toilet is slow to fill and perform the most appropriate repair. If the fixture has hit the end of its typical life span, our team can propose high-efficiency toilet replacement in the U.S.. We’ll help you pick out the replacement model and install it for you. Relax knowing that every job we execute is supported by a 100% satisfaction guarantee! To schedule a visit from us, please call Service Experts Heating, Air Conditioning & Plumbing today. 

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