Why Is My Toilet Slow to Fill?

Is your toilet tank filling more slowly than usual? This is a frequent toilet predicament with multiple possible reasons. Thankfully, none of them are serious concerns or expensive to fix. Follow this guide to get your slow toilet flowing quickly again. 

How to Address a Slow-Filling Toilet 

Understanding why your toilet is slow to fill is step #1 for fixing it. Keep in mind these possible 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 connected to it, which allows you to turn off the water when your toilet is being repaired or replaced. Make sure this value is open by turning it to the left. 

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 water level flowing into the tank. A toilet fill valve may break down, clog or move out of alignment after years of use, preventing the tank from filling properly. Follow these instructions to adjust, unclog or fix the fill valve: 

• Search for the fill valve: Remove 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 linking 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. Modify the fill valve height if needed by twisting the adjustment knob (typical to newer toilets) or loosening the adjustment screw with a flathead screwdriver (required for older toilets). After that, make sure the water level is approximately one inch below the top of the overflow tube. 
• Wash the fill valve: To remove mineral accumulation and other debris from the valve, first shut off the water in the rear of the toilet and take off the fill cap. Then, slowly turn the water back on, cupping your hand over the valve to keep from being sprayed. Let some water flow for several seconds to flush out the buildup. Next, scrub away mineral buildup off the fill cap. If you notice cracks or substantial wear and tear, replace the valve. 
• Clean the valve tube: Dirt lodged in the valve tube could also be to blame. Turn off the water supply and remove the valve hardware. Then, run a thin wire or bottle brush down the tube. Open the water supply slightly to flush away the leftover residue. Reconnect the valve hardware and verify if the toilet fills quicker. 

Waterlogged Float Ball 

The float ball in older toilet models rises with the water level, shutting the fill valve when the tank is full. If the float ball takes on water, it keeps the tank from filling properly. 

Pull up the tank lid and view inside. A partially submerged float ball might be waterlogged. Before you replace the ball, check the float arm it’s secured to. If the arm is pointed too low in the tank, bend it up somewhat to raise 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 might possibly be better to modernize the existing tank components or switch out the toilet altogether. 

Clogged Plumbing Vent 

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

You’ll need to jump up on the roof to look for clogged plumbing vents. Look for long, vertical PVC pipes poking up from the roof tiles. Get rid of any animal nests, deep snow or other obstructions you find to ensure your plumbing works properly. 

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 dilemma could stem from your supply pipes. A problem with the water line itself could restrict your toilet tank from filling correctly. It’s best to hire a licensed plumber to handle 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 identify the reason why your toilet is slow to fill and perform a cost-effective repair. If the fixture has come to the end of its useful life span, our specialists can suggest high-efficiency toilet replacement in the U.S.. We’ll help you find the replacement model and install it for you. You can relax knowing that every job we execute is backed by a 100% satisfaction guarantee! To schedule a visit from us, please call Service Experts Heating, Air Conditioning & Plumbing today.