Why Is My Toilet Slow to Fill?

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

How to Address a Slow-Filling Toilet 

Finding out why your toilet is slow to refill is step #1 for fixing it. Consider these possible reasons and how to deal with each one. 

Partially Closed Water Supply Valve 

Take a peek behind the toilet for the water supply line attached to the wall. You’ll notice a valve connecting to it, which enables you to turn 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 can be found 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 might break down, clog or slip out of alignment after years of use, hindering the tank from filling right. Follow these instructions 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 installed 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: Make sure the fill valve is secure and evenly attached to the tube. Change the fill valve height if needed by turning the adjustment knob (typical to newer toilets) or use a flathead screwdriver to loosen and adjust (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 take out mineral buildup and other gunk 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 keep from being sprayed. Let the water flow for a few seconds to flush out the buildup. Next, scrub away mineral buildup off the fill cap. If you observe cracks or excessive wear and tear, replace the valve. 
• Clean the valve tube: Dirt trapped in the valve tube could also be the culprit. Turn off the water supply and take off the valve hardware. Then, run a thin wire or bottle brush into the tube. Open the water supply slightly to flush away the remaining residue. Re-install 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, closing the fill valve when the tank is full. If the float ball is filled with water, it prevents the tank from filling properly. 

Pull up the tank lid and view inside. A partially sunken float ball could be waterlogged. Prior to replacing the ball, examine the float arm it’s connected to. If the arm is pointed too low in the tank, bend it up somewhat 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 an older toilet design, so it may be better to modernize the existing tank hardware or replace the toilet altogether. 

Clogged Plumbing Vent 

Your home plumbing system uses vents that enable air to enter the pipes. If they become clogged, pressure may build throughout the pipes, stopping the water from flowing. This can, in turn, make your toilet fill slowly or even cause the bowl to overflow. 

You’ll need to jump up on the roof to search 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 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 dilemma could stem from your supply pipes. A leak or blockage in the water line could stop 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 

Is your toilet still not working right? Turn 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 cost-effective repair. If the fixture has reached the end of its useful life span, our company can suggest high-efficiency toilet replacement in the U.S.. We’ll help you decide on the replacement model and install it on your behalf. Rest assured that every job we execute is protected by a 100% satisfaction guarantee! To schedule a visit from us, please contact Service Experts Heating, Air Conditioning & Plumbing today.