
There is nothing more horrifying than using a toilet to go about one’s usual routine only to realize that it won’t flush. You found out too late that the toilet tank is empty and you’re quietly thanking heavens for the toilet paper. Everyone must have experienced this once or twice and for sure, it is one of those things you won’t wish even to your worst enemy.
If you’re having this problem with your toilet, let’s say in the middle of the night, and there’s no one that you can call for these not-so emergency plumbing cases, don’t worry. But first things first. Let’s answer this all-important question. Why won’t your toilet refill with water?
Each time you flush the toilet, the tanks should refill with water. At least that’s how these things should work. Toilets are not very different from a water heater with a water tank, only their reservoirs are way smaller. When the process of refilling those tanks with water gets awry for one reason or the other, and you’re left with a toilet with a water level below the acceptable quantity.
In order to fix that, here’s a list of the toilet parts that may be faulty, damaged, or misadjusted. Taking a closer look at them is the first step to solving this inconvenience. But first, you must familiarize yourself with these toilet parts if this is the first time that you’ll be tackling plumbing problems.
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INFORGRAPHIC HOW TO FIX TOILET THAT WILL NOT REFILL

Why Won’t My Toilet Tank Fill Up With Water
Below are the most common toilet parts that may affect how the tank fills up with water. If any of the parts below are found faulty, then you either must repair or replace these to improve its water flow and tank refilling process.

Fill Valves
Toilets are equipped with fill valves that send out the signal when the tank should be filled and when to stop filling it. These fill valves are mechanical parts that come with nothing more than a tube assembly, but they play a crucial role in maintaining the right water level inside the toilet tank.
It works to control the toilet’s tank water level so that the toilet tank won’t overflow. These parts are easy to spot because they are connected to the tank ball or float, if your toilet still has them, that is. In turn, these valves connect to the toilet cistern.
Main Water Valves
There’s another valve that controls the water into the toilet and this one is connected directly to the water supply of the entire house. Simply put, this valve controls the amount of water that the toilet gets from the main water supply line.
This is something quite easy to check, as this valve can be found very near the toilet. You simply turn the knob clockwise to turn it off and counterclockwise to open it up. Don’t forget to inspect if there’s a leak around the main water valves as well.
Flapper Valves
The toilet flapper valve is found at the bottom of the toilet tank. Its job is to make sure that the water doesn’t empty into the toilet when it’s not in use. If this valve doesn’t seal properly, then it may be the one causing the leak. If your toilet is old, see if this valve has worn out. In case you see any signs of damage, go ahead and get it replaced.
Overflow tubes
Aside from the toilet fill valves, the overflow tubes also play a vital role in the filling of toilet tanks. These large tubes transport excess water from the tank to the bowl to avoid an overflow. These tubes are also easy to find, as they are right at the center of the toilet tank and are connected to the toilet flush.
Flush assembly
One of the common culprits of a toilet not filling with water is a damaged trip lever or flush assembly. We all know that the flush is that wonderful thing that gets the water down the bowl to make things go away. For that reason, we want this one working as perfectly as it should.
If the flush lever, which is also sometimes referred to as the toilet handle, is not positioned correctly, then it could be the one that’s allowing the water to run through the bowl. This will cause the toilet tank never to fill up. A faulty flush assembly is also the reason why you have a running toilet so better check this regularly.
Toilet Float
If the float ball is not working properly, then all it might need is some adjusting. Otherwise, you could end up with a running toilet. An incorrectly adjusted float may cause the toilet’s water level to go higher than usual. When this happens, the water could seep over the tank and into the overflow tube, which in turn, would direct more water into the bowl.
Toilet Bowl
Sometimes, the problem is not the parts but the entire system itself. If you have checked everything and the toilet tank still won’t fill, check the toilet bowl for some cracks or leaks. Maybe there’s a crack at the back of the bowl and you just don’t see it. But for sure, there will be tell-tale signs of water getting on the floor.
Steps on How to Fix Toilet that Won’t Refill or Slow to Refill
Now that you know what could possibly be causing the problem, it would be much easier for you now to fix a toilet that won’t refill. Below is a list of detailed troubleshooting steps that can guide you in fixing your toilet in no time. The steps come in different sections, depending on what is the main cause of the problem.
To use the guide below, investigate the cause of the problem first. Find out which of the parts listed above is faulty and procced to the corresponding troubleshooting steps below. But before going through any of the steps, be sure to turn off the main water supply line and flush the toilet to drain out excess water, if there’s any.
How to Fix the Fill Valve

- Remove the fill valve by holding the shaft and turning its cap counterclockwise.
- Check if there’s debris inside the fill valve seat holes.
- Find an empty cup to serve something like the float cup and put it over the fill valve so the water won’t splash around as you open the toilet’s water supply.
- Remove all debris and unblock the fill valve.
- Put the fill valve cap on and put it back after clearing it of all debris.
- If this fails to solve the toilet problem, replace the entire refill valve.
How to Check for Low Water Pressure

- Check if the low water pressure into the bowl is caused by a weak flush.
- See if toilet tanks are slow to fill up.
- Open the shutoff valve fully to see if the toilet’s tank can now reach the right water level.
- Look for unwanted debris, leaking tubes, or clogged water pipes and address them as necessary.
- Evaluate if the problem is only apparent in your toilet bowl or also on other water fixtures.
- If other fixtures are affected as well, then it may be an issue with the main supply pipe.
- Drain cleaning may be necessary, especially if you must use a toilet auger occasionally.
- If none of these steps work, get professional plumbing services to inspect the main water supply line and the clogged toilet pipes.
- Seek the expert’s help to get your toilet water level back to acceptable levels.
How to Replace the Flapper

- Find the lift chain and unhook it from the arm.
- Remove the pegs that attach the flapper from the overflow pipe and then carefully lift it off.
- Clean the area where the old flapper used to be before installing a new one in its place.
- Be sure to put back the pegs securely and hook the chain.
How to Replace the Overflow Tube
- Check the physical appearance of the overflow tube as this tube is prone to cracking, which may allow the water from the toilet tank to get down to the bowl unnecessarily.
- If you see any damage to this tube, replace it as soon as possible.
- Pull out the tube and install a new one that come in the same size.
- Check the refill tube as well. Refill tubes let the overflow tube know how much water it should allow into the toilet bowl.
- If the refill tube is damaged, you must replace it as well.
How to Replace Flush Valve

- Find where the overflow tube lies on the tank, which is usually connected to the base of the flush valve.
- Replace the entire system, such as the overflow tube and flush valve, but only if both are damaged.
- If the flush valve looks fine, just replace the overflow tube as replacing the flush valve can be a little bit complicated.
- To replace the flush valve, loosen the mounting nut using the right pliers.
- Disconnect the flapper to finally lift the valve out from the toilet tank.
- Replace the flush valve with the same type and size. Using a different sizes or type is not recommended.
How to Adjust the Float

- Before adjusting the float, be sure to check its water level first.
- The ideal placement of the float is around 1 to 2 inches below the overflow tube.
- Do check your toilet tank if there are lines identifying what the ideal water level is. This is a good reference point as you adjust the float.
- Loosen the toilet float with a screwdriver.
- Turn the screws that are found near the fill valve counterclockwise.
- Considering the tank’s water line, find the right spot where the float should lie.
- Loosen or tighten the screws as needed.
- Check and test the ball float level and make the necessary adjustments until you’re confident that it is not sitting too low or too high.
How to Inspect the Toilet Bowl

- Check your toiled bowl for cracks. While cracking doesn’t frequently happen on newly installed fixtures, they could develop physical damage that may keep the water tank from filling.
- See if there’s water on the bathroom floor, as that is a sign that there is a leak somewhere.
- If you suspect your toilet bowl to have a crack, do not use it anymore because it may collapse at any added weight or pressure.
- Shut off the water supply tank and call a plumber right away to replace the toilet bowl immediately.
These are all the quick tips on how to fix toilet that won’t fill. These steps outlined here are quite simple, and you can do most of it all on your own. But while all of these seem easy to do, nothing beats the assistance of a well-experienced plumber who can check any toilet problems and provide the necessary solution to them. These professionals can check not just your toilet tank, but also its water pressure, and other underlying factors before carrying out the toilet repair process in a safe and secure manner. So, the next time you encounter toilet issues beyond your DIY skills, just go ahead a hire a trusted plumber to take care of your woes.
