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Last updated: June 15, 2022
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What does it take for the right toilet fill valve to stand out from the rest? Is it the size, design, material, or price? To end up with a fill valve that is a good fit, you must identify its unique qualities and the specific type of toilet it’s designed for. Our inventory of the best toilet fill valve for each toilet makes it easy for you to make the connection.
For starters, our fill valves are chosen for their solid construction. The materials used in their construction are not only strong, but also chlorine and chemical resistant to ensure you get years of unfailing use. They are compatible with a wide range of toilet models, with many featuring a modern, adjustable cup style design, which makes them the ideal replacement parts for any toilet. They are leak proof, guaranteeing the best toilet experience over years of use. Read on to find out which fill valve is right for your toilet.
Arguably the best toilet flush valve kit, the TOTO TSU99A.X fill valve pack includes the valve, refill tube, clamp, cone washer, and nut. It’s an easy to install unit and connects to the standard 7/8-inch inlet connection. Plus, it has an adjustable shaft, offering up to 7.75 inches in height adjustment, which makes it compatible with all TOTO toilet tanks.
Excellent flow rate means the tank fills up quickly, and in a busy household where the toilet is used frequently, this is priceless. The flow rate is also adjustable, so you can control how quickly you want the tank to fill up after each flush.
This fill valve is extremely easy to install. There are no parts to attach; you only have to slide it as it is into the valve opening.
What do we love it for? The adjustable height that ensures it fits different toilets, most notably, all TOTO models.
What were we disappointed with? That you have to adjust it by a specific number of bumps for each particular toilet to get a good fit – you have to look up the number of bumps your toilet needs in the manual or TOTO website. It would have been good if you only had to turn a lever or knob until you heard it lock into place instead.
More features: 10-inch clearance required, smart tech leak detection, chlorine and chemical resistant, 2-inch flapper replacement, 9-in height adjustment, float lock
NEXT BY DANCO HyrdroRight is a dual flush fill valve that is made in a modern, water-saving design. It’s the best toilet fill valve and flapper for busy households and other facilities, and the cumulative water savings add up to huge conserved amounts at the end of the day. Liquid and paper waste, for example, will see you using up to 70% less water.
While this fill valve fits in standard flush valves, it is not compatible with Mansfield toilets. It also requires a minimum clearance of 10 inches from the highest point of the flush valve opening to the inside of the toilet lid. Installation is straightforward and fast. You’ll spend no more than 10 minutes fitting it in, even if you’re not accustomed to doing toilet repairs.
The fill valve comes with Smart Tech leak detection that alerts you as soon as it detects a leak so you’re never caught unawares by a leak that forces you to shut off the water supply and stop using the toilet until it is fixed.
It’s chlorine and chemical resistant and will not be damaged by the presence of these compounds in your water.
What makes it stand out? Smart Tech leak detection helps you stop leaks before they become a major problem. Chemical and chlorine resistance means you can use this valve with all types of water and not worry about it getting damaging.
Which disadvantages must you keep in mind? They could have modified it to fit Mansfield toilets as well.
More features: quiet fill technology, ASSE and IAPMO listed, 8.5 in height adjustment
The Korky 528PRO is made in a universal design that fits all toilets. It’s compatible with all major toilet brands, so chances are, it will fit your toilet, regardless of what brand or size it is, thanks to an 8.5-inch height adjustment that ensures you get the right fit for your toilet.
The best toilet fill valve for high pressure in its price range, it’s designed to operate quietly and does not have the loud noises that let occupants in the farthest corner of the house know you’ve just flushed the toilet. It also refills fast, such that if someone has to use the toilet shortly after it’s been flushed, they won’t wait around for the tank to refill.
We have to say that its quality is outstanding. Although it’s made from plastic, it feels as solid and performs as well as any brass part would. Not surprising, because this valve is ASSE and IAPMO listed and meets all the regulatory standards for quality and performance.
This Korky fill valve is very easy to install, with minimal parts that need attaching. Because of this, you can fit it in even if you’ve never fixed a fill valve before.
Why did it make our list? The universal fit, and by extension, height adjustment that makes it compatible with all toilets.
What is not ideal about it? That the flow rate isn’t adjustable for greater water efficiency.
More features: adjustable body height, mounting hardware included, fit for 2-piece toilets
The AmazonBasics Universal Toilet Fill Valve, which is the best toilet tank fill valve you can get at its price point, is built in a standard universal design that fits most toilets. However, it is designed for 2-piece toilets only. It comes with a bottom connector for the cistern, making it an ideal all-in-one replacement unit. Its shaft is adjustable, so you can raise or lower it to match the water level in your tank.
It comes complete with all the mounting hardware for easy installation. The accompanying manual provides simplified instructions showing you how to install the unit properly. While the installation is easy, for someone who’s never installed a toilet fill valve before, the manual can seem scanty and unhelpful since it isn’t very detailed.
This is a fairly new unit, having been introduced in the market in January 2020, so it doesn’t have the benefit of a long track record to back it up. But the quality of the plastic it’s made out of is solid, and from the few months we’ve used it, it was perfect. It’s backed by the basic AmazonBasics 1-year warranty nonetheless, should you need to replace or return it.
What stands out? The universal design and adjustable height that make it fit for most toilets.
What cons did we manage to find? Sadly, it only fits 2-piece toilets.
More features: quiet fill, multiple fill rate inserts, height adjustment
The Kohler Genuine Part Gp1083167 is a solid unit built with quality materials. You can tell by how heavy and thick it feels in your hands. This fill valve is height adjustable. Just adjust the shaft to match the height of the valve you are replacing and it will work fine. If you had removed the old fill valve earlier and disposed of it, use the water level in your tank to gauge how tall the fill valve needs to be, and then adjust it accordingly.
Among the unique features in this unit are the multiple fill rate inserts, which enhance water conservation and boost performance. It’s also quiet, meaning you won’t hear the sound of flushing or the tank filling up from afar.
This Kohler flush valve is easy to install and doesn’t take much time to fix. However, the instructions are not detailed, which can be frustrating for someone who has never installed a toilet fill valve before.
Why did it make our list? That it has multiple fill rate inserts to optimize performance. The different fill inserts also give you the option to conserve as much water as you like.
What is not ideal about it? The manual could have been better structured and more detailed.
The American Standard 3174.105-0070A Champion is designed to fit all Champion toilets, including the oldest models.
It may not necessarily be the most water efficient unit, but this flush valve saves a considerable amount of water, given that it does not sit at the bottom of the tank, and therefore, retains about 4 inches of water after every flush.
It has a 7-inch tube and measures 3.4 inches in chain length. The shaft is not adjustable, but this should not be a problem when replacing a fill valve in a Champion toilet.
Installation is a breeze, given that you only need to lift the fill valve off its base and slide it into the toilet base. It comes with the valve body to tank seal and flush valve flap seal. However, it does not come with the seal that sits between the tank and the toilet. So you would need to buy that separately if the old one is worn out. Without this, you’ll experience leakage as soon as you’re done with the installation.
What are its best features? Easy installation, takes only minutes to fix.
What could be improved? It would save us time and effort if they included all the gaskets needed for the installation.
More features: 2-in inlet connection, built-in Microban fights bacteria, chlorine and hard water resistant
The Fluidmaster 402CARHRP14 PerforMAX toilet flush valve is designed to fit in 2-inch flush valve toilets. This universal valve adjusts between 10 and 15 inches, making it the ideal replacement for any toilet as it fits most toilet models.
This fill valve is chlorine and hard water resistant, qualities that safeguard it from premature wear, ensuring that it sustains its performance and remains functional for longer. It also comes with the proprietary built-in Microban technology, which gets rids of bacteria that causes the flapper to break down, meaning the flapper lasts longer, and you get more years out of the unit as a result. The flapper itself is constructed in a solid frame that prevents twisting and phantom flushing.
This Fluidmaster fill valve is designed to use 1.6 gallons per flush or less. It also has a flow regulator that slows down the refill rate and keeps the noise level low. To give you control over how much water the toilet uses in each flush, the valve comes with a dial that you can turn to adjust the toilet flush.
What do we love it for? The anti-bacteria flapper mechanism and chlorine and hard water resistance, which minimizes wear.
What were we disappointed with? It could be modified for use with 3- and 4-inch flush valve toilets.
Things to Consider
Owning a toilet fill valve that works seamlessly begins with choosing the right kind of fill valve. And for this to happen, you must know what makes a good fill valve, including the specific features that make it effective in its job. In this next section, we’ll tell you what these features are and show you how to evaluate each fill valve to get the best of these features.
What is toilet flush valve?
This is the component inside a toilet cistern that is responsible for allowing water to pass into the bowl when you flush the toilet. Modern flush valves come with a built-in overflow, which means: should the flush valve malfunction, the overflow will make its way through the flush valve center and into the bowl, allowing the toilet to flush as usual.
They are also button-operated and usually have a dual flush mechanism. When you push the button, the plug/flapper opens and allows a pre-determined amount of water to flow into the bowl, after which it automatically shuts. The dual flush mechanism determines the amount of water to use to flush the toilet. For liquids, it allows a half-flush, and for solids, it allows a full flush.
The standard flush valve size is 2 inches, but we also have 3-inch and 4-inch valves. These bigger sizes allow more water to pass into the bowl, filling it faster. A variation of the 3-inch flush valve is the 3-inch tower flush valve, which is made in a tower design and uses a vertical seal to control water flow instead of a plug/flapper.
How to install a toilet fill valve
Remove the toilet lid.
Turn off the water supply and flush the toilet.
Remove the base the fill valve comes in, and then insert the fill valve into the base of the toilet. Reach behind the refill tube and snap the lock ring into place.
If the fill valve toilet base is in bad shape, replace it before fitting in your new toilet fill valve.
Attach the refill tube to the old refill tube and adjust the new fill valve to attain optimal water level.
Turn on the water supply valve.
Check for leaks and flush the toilet to test.
Make the adjustments needed to rectify installation errors, if any.
After confirming that the fill valve is working properly, place the toilet lid back on.
Prices for toilet fill valves start at $8-10 and can go as high as $100. The universal type is considerably cheaper, with prices averaging $15 to $25 at most. Fill valves that are model and brand specific tend to be more expensive and account for the $80-100 price range. None is better than the other, but the universal type offers convenience at a low price, which few of us would pass up.
Features to consider while buying the best toilet fill valve
Below are the features you should look at when choosing a fill valve.
Among modern toilet fill valves, the diaphragm is mainly found in fill valves made from plastic. But it’s also used with brass fill valves, complemented by plastic buttons. It’s responsible for controlling the flow of water and uses differences in pressure levels at various points to achieve this. As the diaphragm opens, high pressure near the outlet pipe forces water out into the bowl, and as it closes, the pressure begins to fall and water flow diminishes.
Plunger and ballcock types
Toilet fill valves come in 4 main ballcock types. These are:
Plunger/piston-style fill valves, which have a floating ball that’s attached to a lever. The lever opens and closes the plunger stem.
Diaphragm ballcocks, which rely on a diaphragm seal to control the flow of water in and out of the tank. One of the biggest advantages diaphragm fill valves have over other types of ballcocks is that they have a built-in anti-siphon mechanism to prevent the back flow of water from the toilet tank back into the fresh water supply, which can happen when there is low pressure in the water supply line.
Float-cup fill valves, which have an O-shaped floating cup that is attached using a metal spring. The spring is then connected to an actuating rod. To control the water level in the tank, you have to adjust where the actuating rod connects to the float cup.
Floatless fill valves, which are typically attached to the bottom of the tank. They rely on a diaphragm pressure-sensing mechanism to control the inlet valve, and in turn, water flow.
Ensure that the toilet fill valve you’re considering buying is compatible with your toilet. This means you should know your toilet dimensions and the kind of valve enclosure it has. If unsure, choose a universal toilet fill valve. Universal fill valves are designed to fit all toilets and hardly disappoint. You may need to adjust the height to get a good fit, but this is never a challenge. Alternatively, choose a toilet fill valve that is built specifically for your type of toilet.
A high refill speed means the tank fills up fast after the toilet is flushed. A valve that refills the tank quickly is desirable, particularly in busy households where the toilet is used frequently. If you are hosting guests, you also want to have a high tank refill speed given that you’ll have people using the toilet throughout, and you wouldn’t want to have this holding up the line of toilet users. Fortunately, most modern toilet fill valves have a high refill speed, so this won’t be a problem. Still, the speed varies between models. It’s good to compare different units to see which offers the highest speed.
In some fill valves, noise is subdued to the extent that you cannot tell when the toilet is flushed or when the tank is refilling. The degree of noise cancellation varies from model to model, so it’s a good idea to compare how quiet different units are, and then pick the one you feel meets your expectations. Note that it’s impossible to eliminate all noise 100%, and so the valve will emit some sound. It need not be so loud that it is audible from other rooms, however, and this is where you use your judgment to determine how loud is too loud for you.
Choose a toilet fill valve that is easy to install because you’ll have a lower possibility of making installation errors. If the fill valve is complex and a headache to install, you are more likely to install it incorrectly and end up with a fill valve that doesn’t work at all or one that doesn’t work like it should. Manufacturers of modern toilet fill valves have taken the guesswork out of the installation process by making fill valves in simple designs that are easy to install. These come with step-by-step installation instructions, often accompanied by illustrations, and sometimes, videos (available on the manufacturer or seller’s website).
If you’ve been using older toilet fill valves, you may have concerns about the newer container-type fill valves on sale. However, these cup fill valves are what you find in most modern toilets, and they are designed to offer a universal fit. The cup measures between 7 and 13 inches, and can be adjusted to fit all kinds of enclosures.
Toilet fill valves are designed to last. You only need to look at some of the guarantees to know that this is true. Fill valves like NEXT BY DANCO HyrdroRight and Korky 528PRO come with a 5-year and 7-year guarantee respectively. This doesn’t mean that all fill valves have such strong backing from their manufacturers. There are plenty that only come with a 1-year warranty, which isn’t to say that their performance goes down after one year. What’s more important is to get some form of assurance from the manufacturer or seller when buying, and this varies greatly. Choose the guarantee you’re most comfortable with. Some people are okay with a 1-year guarantee, others prefer something more extensive.
To ensure the highest quality, ABS plastic is often used to make fill valves. And because this material is durable and corrosion resistant, it provides the longevity and reliability you desire in a toilet unit. Avoid poor grade plastic as it wears easily, forcing you to replace the fill valve sooner than you should. The problem of poor-quality plastic only becomes an issue when dealing with non-brand fill valves where details of the materials used to make the product are not included. And because the brand/manufacturer is not listed or known, you have nowhere to direct any questions you may have about the product.
The best toilet fill valves are leak proof. You should not have any leaks after installing the fill valve. If you experience leaks after fitting in the fill valve, it’s likely that you did not install it correctly. With time, though, leaks are bound to happen in the toilet. So always watch out for them and repair them as soon as they appear before they become major and make the toilet unusable. Some fill valves like NEXT BY DANCO HyrdroRight have leak detection technology which signals when they detect a leak. Sometimes the leaks are so small you wouldn’t tell they are there. Having such a system in place helps you arrest the problem before it escalates and attracts excessive repair costs.
Begin by shutting off the water supply and flushing the water that’s in the tank. Use a piece of cloth to wipe off the remaining bits of water in the tank. Wet a sponge in soapy water and use it to wipe down the valve, and then wipe it down with a clean piece of cloth to rinse it of the soap. Avoid using chemicals and harsh abrasives for the task. Once the fill valve is all cleaned, restore the water supply.
A good quality toilet fill valve should last at least 5 years. Often, they last longer. But if you notice changes in its performance, you should go ahead and replace it. Here is how to tell if it’s time to change your fill valve: if there are leaks, if you notice weak toilet flushes, if you notice ghost/phantom flushes, or if there are weird noises coming from the toilet.
Check the height and overall dimensions of the fill valve to ensure that it will fit in your toilet. This means you must know the dimensions of your toilet, and that is easy to measure. If the fill valve height differs from your toilet measurements, check whether it has an adjustable shaft and by how many inches. Then cross check this with your toilet measurements to determine whether the fill valve will be a good fit.
Our Editor’s Choice is TOTO TSU99A.X, a unit that fits all TOTO toilets, and which stands out for its adjustable refill rate, adjustable shaft, and easy installation. We like that the instructions are comprehensive and clear and that it comes with all the hardware needed for the installation.
Our second choice is NEXT BY DANCO HyrdroRight, which is defined by its water-saving design and quick installation. Other top-rate features are its self-cleaning mechanism, leak detection system that warns you of leaks early enough, and the chlorine and chemical resistant materials it’s made of, which protect against chemical wear.
Number three in our best toilet fill valve list is Korky 528PRO, a universal fill valve with an 8.5-inch adjustable height and a high refill speed. Among its outstanding features are solid build quality and materials, quiet operation, and easy installation. It’s ASSE and IAPMO listed, which further confirms its uncompromising quality and performance.