Reasons For Slow Filling Toilet and How to Fix Slow Filling Toilet Tank

Having to wait longer for your tank to refill just to pull the flush lever to activate the next cycle of flushing can be pretty frustrating. Does it feel like your toilet tank is taking forever to fill up and you’re wondering what the issue might be? A few reasons can cause your toilet to refill slowly and we will give you some tips on how to fix that slow filling toilet tank.

Your toilet tank should complete its refill in just about a minute depending on the water supply pressure you’ve got in your house. However, once this refilling process lingers longer than it should, then you’ve got an issue.

This slow filling toilet can be pretty daunting and can have you wondering what’s wrong with your toilet. Not too worry because we will be giving you the possible reasons why your toilet is slow to refill. Then we will give you troubleshooting tips on how to fix your slow filling toilet tank. So, come on closer, and let’s get you fixing.

Reasons Why You Have a Slow Filling Toilet

Now, to the possible reasons why your toilet tank fills slower than ever; the reasons might be one of these stated below:

1. Fill valve                 

When your toilet tank fills slower than it should, you might want to check your fill valve. This toilet fill valve is responsible for the way water fills up inside the reservoir. So, the fill valve works by ushering water flow into the toilet tank after a flush cycle and it remains on until the toilet tank has filled up to its appropriate level.

As time elapses, fill valve can get worn-out, get clogged, or the fill valve can move out of its position. This toilet issue can cause your toilet tank to refill slowly.

2. Waterlogged float ball issues

A float ball encourages water to keep flowing inside the toilet tank until it attains a certain level. Once the float ball is waterlogged, there will be a toilet issue and the tank won’t refill efficiently.

So, this can impede the right amount of water from moving into the toilet tank. Or, the manner in which water fills the tank can become slow.

Your float ball needs to be floating near the upper part of the tank and if it’s not, then you might be dealing with a waterlogged float ball.

Note that float ball is an old-style and you may want to consider going for the modern-style if your float ball requires replacement.

3.    Low water pressure and leaks

Your slow filling toilet tank can be as a result of low water pressure and leaks. Once there is a leak in any of your piping, it can result in low water pressure, thereby causing your tank to fill slowly. The reason for the leak can be from your pipe bursting or your plumbing can be corroded. Homes that are old with outdated plumbing often experience this issue more.

Again, regarding the water pressure, if many parts of your house have low water pressure, it can cause your tank to fill slowly.

4. Partially opened water supply valve

A partially opened water supply valve can also cause your tank to fill slowly. This is why you should also check your water supply valve which is close to your toilet seat to ensure it isn’t closed or partially opened.

5. Clogged plumbing vent issues

One possible reason why your toilet tank is taking longer to fill may be that your plumbing vent is clogged. So, if your plumbing vent is clogged, there will be less chances for air to escape from the tank. Hence, this can cause water to take more time to refill in your toilet tank inhibiting your toilet flush.

The opening of your plumbing vent stack is usually outdoors on the roof. Therefore, the outdoor position where your plumbing vent is can predispose it to outdoor elements. Hence, vent clogging which blocks the opening can happen through debris, dust, leaves, and so on.

Vent stack helps regulate air pressure in the plumbing system of our homes. So, once the vent is blocked, it minimizes or totally decreases the air pressure. This means that where there is supposed to be water, the water will be absent. It could also mean that debris has built-up in your water supply valve.

Hence, you have little to no water in the toilet tank because the water that’s supposed to be there just continues to move down the pipe.

Also, once your bathroom sink is slow to drain, you have a slow draining toilet, or if multiple areas in your house take longer to drain, it’s a big sign that you have a clogged vent.

How to Fix Slow Filling Toilet Tank Step-by-Step Guide on

Now that we have given some possible reasons why your toilet tank may be filling slowly, let’s now look at how to fix slow filling toilet tank.

Before you begin troubleshooting how to fix that slow filling toilet tank, it’s necessary you do some investigation first. This investigation will let you know which part of your toilet is faulty.

Also, before you commence working inside your toilet tank, ensure the water supply is shut-off. The toilet will also need to be flushed so that you can have easy access to it.

1. Fill valve troubleshooting tips

So, once you’ve identified that it’s the fill valve that is the problem, take the steps below to solve the issue. Check if the fill valve has worn-out or if it’s out of position.

Step 1 – Find the fill valve

Lift up the toilet tank lid and identify the fill valve. You should find this on the left area of the tank. Find out where the tank cap is and you should see the fill valve. If your toilet is an old type, you’ll require a flat-end screwdriver to loosen up the adjustment screw. Then if your toilet is the modern type, you should be able to use your hand to adjust the fill valve knob so more water can move into the tank.

Step 2 – Necessary adjustments

Now, the adjustment required will be to raise the fill valve so extra water can move into the tank. So, to encourage more water into the tank, turn the screw clockwise. Conversely, to minimize the water flowing into the tank, turn the screw in a counter-clockwise motion.

Step 3 – Testing

After doing the steps above, it’s time to test flush the adjustments you’ve done to determine if it resolves the issue.

2. Waterlogged float ball troubleshooting tips

Material required

If you’ll need to entirely replace your float ball, you’ll need to purchase a new float ball.

Step 1 – Fixing

You’ll need to determine if your float ball requires fixing or replacement. It needs fixing if the ball is lying too low in the toilet tank. So, simply bend the arm a bit upwards aiming to lift the ball higher inside the toilet stank. Then more water can flow in to help your toilet flush once you do this and everything should be fine.

If this first step doesn’t work for your slow flushing toilet, then you should move to step 2.

Step 2 – Replacement

So, if the first step doesn’t do the trick and you’ve determined that your float ball is still the issue here, then you’ll need to purchase another float ball. Therefore, do the needful and get a new float ball for replacement.

3. Low water pressure troubleshooting toilet tips

Once you have low water pressure in multiple areas of your home, then you might consider installing a booster tank. This can help increase the water pressure in the areas of your home.

However, if there’s any pipe leak, reach out to a professional plumber check for your pipes in this case.

4. Partially opened water supply valve troubleshooting tips

It’s pretty easy troubleshooting a partially opened water supply valve. Follow the steps below to solve this issue.

Step 1

You should likely find your water supply at the bottom left part of your toilet unit close to your toilet bowl. So, locate this valve and check to see if it’s closed or partially opened.

Step 2

If you have a partially opened water supply valve, do well to open it fully. This will enable adequate water flow into your toilet tank fast and refill adequately.

Step 3

Next, it’s time to test by flushing to see if the checks and adjustments above worked. If it worked, then your toilet is good to go and if it didn’t work you’ll need to investigate further to find out other causes for your slow filling toilet tank.

5. Clogged plumbing vent troubleshooting tips

Step 1 – Inspect your vent

If you suspect the toilet issue you have is caused by a clogged vent, you can check the vent opening on your roof – that is, if it’s safe to do this. So, if you notice the blocked vent is only at the opening of your vent, you can climb your roof if it’s safe.

Step 2 – Remove debris and do a test

Then remove the debris that is covering and blocking the vent. Once you’ve done this, test by flushing to see if what you did worked.

Step 3 – Get professional help

However, if the issue isn’t resolved, we recommend you get professional help right away once you’ve determined that the issue at hand is still a clogged vent.