Why Is My Toilet Slow to Fill?

Is your toilet tank filling more slowly than usual? This is a common toilet problem with multiple possible reasons. Fortunately, none of them are serious concerns or costly to correct. Follow this guide to get your slow toilet working efficiently again. 

How to Fix a Slow-Filling Toilet 

Understanding 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 connected to the wall. You’ll notice a valve connected to it, which enables you to shut off the water when your toilet is being repaired or replaced. Make sure this value is open by turning it to the left. 

Trouble with the Fill Valve or Tube 

The fill valve, which can be found close to the top of a vertical tube-shaped part in the toilet tank, regulates the water level flowing into the tank. A toilet fill valve might break down, clog or reposition out of alignment after years of use, preventing the tank from filling right. Follow these tips to adjust, clean or fix the fill valve: 

• Find the fill valve: Lift the toilet tank lid and find the fill valve inside. It’s normally secured 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 connected to the tube. Modify the fill valve height if required by turning the adjustment knob (found in newer toilets) or loosening the adjustment screw with a flathead screwdriver (required for older toilets). After that, make sure the water level is roughly one inch below the top of the overflow tube. 
• Clean the fill valve: To eliminate mineral accumulation and other dirt from the valve, first shut off the water in the back of the toilet and take off the fill cap. Then, slowly turn the water back on, cupping your hand over the valve to prevent from being sprayed by the water. Let the water flow for a few 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: Debris inside the valve tube could also be the culprit. Shut off the water supply and take off the valve hardware. Afterward, run a thin wire or bottle brush down the tube. Turn back on the water supply slightly to clean 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 whenever the tank has filled. If the float ball is damaged or punctured and fills with water, it keeps the tank from filling efficiently. 

Pull up the tank lid and look inside. A partially sunken float ball might be waterlogged. Before running out to buy a new ball, look at 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 this doesn’t work, then it might be time to just replace the component entirely. Just remember that this is old toilet technology, so it may be better to upgrade the existing tank hardware or change out the toilet entirely. 

Clogged Plumbing Vent 

Your home plumbing system includes vents that allow air to enter the pipes. If they end up being clogged, stress may build inside of the pipes, stopping 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 need to get on the roof to search for clogged plumbing vents. Look for long, vertical PVC pipes poking up from the shingles. Do away with any animal nests, deep snow or other obstructions you find to guarantee that your plumbing can function as intended. 

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 water line leak could restrict your toilet tank from filling properly. It’s best 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 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 average life span, our team can recommend high-efficiency toilet replacement in the U.S.. We’ll help you find the replacement model and install it on your behalf. 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.