
The Hayward DE4820 ProGrid vertical DE pool filter has been engineered to produce crystal clear water while being very low maintenance. DE pool filters clean down to 2 microns, which is phenomenal and the reason why the Hayward DE4820 ProGridΒ is so effective. You won’t be disappointed, and if you don’t believe me just read comments from customers online.
In this article we cover a wide range of topics, including: Different types of pool filters, how does a DE filter work, not only do we cover the Hayward DE4820 in detail but we also give you an overview of all of the other models in the series β on top of all of that we have diagrams, videos and other information that we know you’ll find helpful.
Table of Contents...
- 1 Intro | Hayward DE4820Β β ProGrid Series
- 1.1 Types of Swimming Pool Filters
- 1.2 How Does a DE Pool Filter System Work?
- 1.3 Hayward DE4820 ProGridΒ | Vertical DE Pool Filter
- 1.4 The Series | Hayward ProGrid Vertical DE Pool Filter
- 1.5 Which ProGrid DE Pool Filter Is Right For You?
- 1.6 Common Mistakes People Make
- 1.7 Hayward C9002SEPΒ Β | D.E. Cartridge Filter Separation Tank
- 1.8 Related posts:
Intro | Hayward DE4820Β β ProGrid Series
When you slip into your pool you expect it to be clean at all times. You’re not going to have fun swimming laps if you know you’re eating dirt and grime at the same time. If you have a family you want them to be safe when they’re splashing around having fun.
In order to achieve your goal of having clean water at all times, you’ll need the services of a pool filter like the Hayward DE4820. Once it’s set up you’ll never have to worry about swimming in dirty water again, but there is always something most people need to know first.
Quick Overview of Hayward ProGride DE Filter Models:
- Hayward DE2420 β 24 sq. ft.Β | 48 GPM
- Hayward DE3620 β 36 sq. ft. | 72 GPM
- Hayward DE4820 β 48 sq. ft. | 96 GPM
- Hayward DE6020 β 60 sq. ft. | 120 GPM
- Hayward DE7220 β 72 sq. ft. | 144 GPM
Hayward DE4820 ProGrid | Common Features on All Models

General Features (ProGrid Series) :
- Filter tanks are made from the durable materials to meet the demands of the toughest applications and environmental conditions.
- High capacity, rapid release manual air relief valve bleeds air with a quick quarter turn of the lever.
- Heavy-duty, tamper-proof, one piece flange clamp securely fastens tank top and bottom and allows quick access to all internal components.
- Vertical grid filter for in-ground pools and spas of all types and sizes : Residential/Commercial.
- Inlet diffuser elbow distributes flow of unfiltered water evenly to all filter elements and provides even distribution of D.E. (diatomaceous earth) to grids.
- Full-Size 1.5β Integral Drain enables fast, 100% clean-out and relatively easy flushing.
- Convenient valve and plumbing options allow for customized control; heavy-duty, tamper-proof, 1-piece flange clamp securely fastens tank top and bottom. Allows quick access to all internal components without disturbing piping or connections.
- 2-inch full-flow internal piping and plumbing for less resistance to flow and maximum performance.
- The Hayward DE4820 is designed for 48 sq.ft. effective filtration area.
Documents for the Hayward ProGrid Vertical Grid Pool Filter Series:
- View or download the MANUAL.
- View or download the BROCHURE.
- View or download the PARTS LIST.
Types of Swimming Pool Filters
If you look online you’ll see there are a few different kinds of swimming pool filters, so let’s give you a look at the ones you’ll see popping up:
- D.E. (Diatomaceous Earth) Pool Filter
- Cartridge Pool Filter
- Sand Pool Filter
At the end of the day, all of these pool filters carry out the same job. They help keep your swimming pool free of dirt and debris even though they go about things a little differently. You don’t need to backwash cartridge filters. Sand filters require the least amount of maintenance. It’s easy to go on and on, but ultimately DE pool filters like the Hayward DE4820 are the top choice for one big reason.
Pentair Option | Pentair FNS Plus β 18009 DE Pool Filter

*We like to give you, our readers, alternatives and inform you of products worth your money, so, in this case Pentair makes the FNS Plus and Quad D.E. Cartridge Style series. See products below.
In the end, you have to decide what’s the right decision for you and since we don’t know your pool setup or budget or brand loyalty we feel it’s our duty to provide you with accurate information β that’s our goal here; provide you the data so you can make an informed decision.
β It All Comes Down To The Micron Range
The best pool filters will trap the most amount of particles possible instead of letting them flow back into the pool. To make this easy to understand you should turn your attention to fishing nets. What do you think is going to happen if a net has large holes? Lots of little fish would be able to escape. If you took another net with tiny holes it would catch nearly everything that came into its path.
When we talk about pool filters the unit we use is the micron. A smaller micron number means the pool filter will be able to trap much more particles, and the DE filters are head and shoulders above the rest. We’re finally going to look at those filters in more detail, but first let’s compare the micron range of them all so you’ll see how much more effective they are:
- DE Pool Filter = 3-5 microns
- Cartridge Pool Filter = 25-100 microns
- Sand Pool Filter = 20-100 microns
Please Note: With the naked eye it’s possible to see something about 35 microns in size, so a DE pool filter will trap particles so small you would never have knew they existed. Although the other types of filters can catch particles less than 35 microns in size, it’s possible if they’re grouped together they could be visible.
What Exactly Is Diatomaceous Earth?
We’re going to be spending a lot of time talking about DE pool filters like the Hayward DE4820, so it’s going to be helpful if you actually know what diatomaceous earth is. It’s a rock composed of fossilized diatoms, which are chemically inert organisms algae-like in nature. The main thing you need to know is the substance can trap more particles than something like sand, but let’s look at how it works.
How Does a DE Pool Filter System Work?
The way the entire system works can be quite complicated, so we’re going to break it down into a few specific stages. Once you’ve read through them all you’ll have a good idea of how everything works:
- Pouring In Your DE
- Filter Traps Particles
- Backwashing The System
- Replace Your Missing DE
β Pouring In Your DE
This might be the first step in the process, but don’t forget by this point your DE pool filter is already set up in your garden. You would take your diatomaceous earth and pour it inside your skimmer, which would then be pumped through the pipes and into your DE filter. The amount of diatomaceous earth you pour into the skimmer will depend on the size of pool filter you’re using, but if we use the Hayward DE4820 as an example you would need 6 pounds.
Video | Adding the Right Amount of Diatomaceous Earth
β Filter Traps Particles
If you opened a Hayward DE4820 up you would find an assembly of grids. When the diatomaceous earth is pushed into the filter it will coat these grids. Now the water from your swimming pool will pass through the filter and it needs to squeeze through these grids. There is enough space to let the water pass through, but all the dirt and debris will stick to the diatomaceous earth and over time it will build up.
β Backwashing The System
Eventually it will reach a stage where the buildup is so bad the water won’t be able to pass through easily. Once the pressure gauge on the front of the filter hits 8-10 psi you’ll want to backwash the system, which reverses everything by sending water through the filter backwards. When you turn the valve the water will flush out all the dirt and debris along with the diatomaceous earth. After the water turns clear you can turn the valve back to its original position.

β Replace Your Missing DE
Now your grids are completely rid of everything, so you’ll need to start the entire process again. Take your 6 pounds of diatomaceous earth and pour it into your skimmer. It will go into the filter and latch onto the grids. Hopefully you can see the entire system works in one big loop. The first and final step are the exact same, so this process will keep on repeating itself until a little later on when we’ll discuss how to give your pool filter’s grids a proper clean.
Please Note: Diatomaceous earth is a carcinogenic substance with the ability to cause your body a great deal of harm. You don’t need to wear gloves when you’re handling it, but it’s imperative you don’t ingest it so a face mask is a must. It’s terrible for your eyes too, so safety goggles should always be worn.
β There is a food-grade version of diatomaceous earth that you can actually ingest. Many people swear by it and use it in various ways, but there is a difference between the type used for pools and other applications and the food-grade. If you want to learn more then read our in-depth article on diatomaceous earth. I think you’ll be surprised at all of the uses for this product. It’s rather impressive β it even kills insects.
Hayward DE4820 ProGridΒ | Vertical DE Pool Filter

Anyone who has a swimming pool will already know about Hayward. They are the king of the industry and they’ve been going strong for over 80 years. During those years they’ve been more innovative than every single competitor they have come up against, which they put down to listening to their customers and giving them what they want. The way they came up with their ProGrid Vertical DE Pool Filter series is no different.
We’re going to talk about the entire series in a while, but to be honest there isn’t a great deal of difference between each one. Instead of giving you a pile of information about every single one, we’ll focus on the features of the Hayward DE4820 because it’s the most popular. Afterwards we’ll then cover the rest of the series, but here is what you want to know about the DE4820:
- It’s Constructed Of Perma Glass XL
- You Can Access The Grids Easily
- Distributes All The Water Evenly
- Large 2-Inch Internal Plumbing And Piping
- Pressure/Cleaning Cycle Indicator Gauge
- Rapid Release Manual Air Relief Valve
- Superior Filter Performance Every Time
- Comes With A 1-Year Limited Warranty
It’s Constructed Of Perma Glass XL
Once your Hayward DE4820 is set up it’s not going anywhere, so it needs to be able to handle itself. Perma Glass XL is a glass reinforced copolymer. Don’t let the glass in the name fool you, because it’s extremely strong and durable.
This will help tremendously if you live in areas where it gets a little wild as far as the weather is concerned. One of the other big bonuses of the Perma Glass XL is the fact it will last for years, although you should winterize it.
You Can Access The Grids Easily
A flange clamp securely attaches the bottom of the tank to the top part, plus it’s worth pointing out this is tamper-proof to stop anyone from opening it accidentally. The location of the clamp will save you so much time too.
It will take you less than a minute and you’ll have access to the inside of your Hayward DE4820. If it was attached in a different way you might have had to disturb the pipes and connections, which would have made everything a lot more difficult.
Please Note: Once you’ve taken the bolt off you might find it’s still not going to let you inside. This is because the clamp has been sitting so long it’s now stuck in place. It’s perfectly normal for this to happen and you should be able to loosen it up straight away with a screwdriver.
Distributes All The Water Evenly
If you picture all of the water pouring into the DE filter it’s hard to figure out how it could be evenly distributed. Hayward have figured out how to do this perfectly, which they did by adding an inlet diffuser elbow.
Thanks to the unfiltered water being spread out evenly among the grids it allows for much smoother operation of the unit. It also means you don’t need to replace certain grids more than others because they’re taking the brunt of the assault.
Large 2-Inch Internal Plumbing And Piping
You want the least resistance possible when the water is moving through the DE pool filter, so Hayward gave the DE4820 2-inch free-flow internal plumbing and piping which you won’t find on some other models.
In the end you have a pool filter that has less resistance to the flow of water, which will be different depending on your pool. It also helps the Hayward DE4820 deliver maximum performance at all times.
Pressure/Cleaning Cycle Indicator Gauge
If you don’t maintain your DE pool filter it’s going to ruin a couple of things. The first being the unit itself, because it’s not going to last for multiple years if you don’t take care of the grids. It will also hurt your swimming pool.
Hayward came up with a few ways to let you know it’s time to backwash the system. There is a pressure gauge to tell you when it’s clogged up, plus the cleaning cycle indicator will make sure you don’t wait too long between backwashes.
Please Note: It’s sometimes hard to keep your eye on the pressure gauge to make sure it’s not hit 8-10 psi. Some people like using a permanent marker to draw a line on the face on the pressure gauge, because it’s easier to see once it’s sitting at the correct psi.
Rapid Release Manual Air Relief Valve
Once you’ve turned your pump off air will be allowed to build up in the system. Should you then turn the pump back on it will create a huge amount of pressure, which could easily cause damage to your filter and the air will fight the water for space.
To prevent anything bad from happening Hayward have included a rapid release manual air relief valve, so you’ll be allowed to get rid of the trapped air within seconds. A quick quarter turn of a lever will bleed the air sitting inside the unit.
Superior Filter Performance Every Time
You might have noticed a DE pool filter is what you would call an extremely passive piece of equipment. It doesn’t have anything to do with electricity. There are also hardly any moving parts, with none of them being more than levers.
When you buy the Hayward DE4820 you’re really paying for the excellent ProGrid vertical filters. They are without a doubt the best available today and are covered in a custom fitted monofilament polypropylene filter cloth.

Comes With A 1-Year Limited Warranty
As soon as you’re about to buy something more expensive than a chocolate bar it’s natural to start wondering what will happen if something goes wrong. When you buy a product from Hayward there is no need to worry as it will come with a warranty.
The Hayward DE4820 comes with a 1-year limited warranty, and will cover defects in materials and workmanship. It will also cover parts if they become defective, although certain things like negligence won’t be covered so you’ll need to read the manual.
The Series | Hayward ProGrid Vertical DE Pool Filter
We mentioned earlier on the Hayward DE4820 isn’t the only unit in the ProGrid Vertical DE Pool Filter series. There are five models for you to choose from. Let’s look at the differences between them all:
- Hayward DE2420 β 24 sq. ft.Β | 48 GPM
- Hayward DE3620 β 36 sq. ft. | 72 GPM
- Hayward DE4820 β 48 sq. ft. | 96 GPM
- Hayward DE6020 β 60 sq. ft. | 120 GPM
- Hayward DE7220 β 72 sq. ft. | 144 GPM
Hayward DE2420 ProGrid | Vertical DE Pool Filter
- Effective Filtration Area = 24 sq ft
- Diatomaceous Earth Required = 3 pounds
- Height = 32.5 inches
- Public Design Flow Rate = 48 GPM
Hayward DE3620 ProGrid | Vertical DE Pool Filter
- Effective Filtration Area = 36 sq ft
- Diatomaceous Earth Required = 4.5 pounds
- Height = 34.5 inches
- Public Design Flow Rate = 72 GPM
Hayward DE4820 ProGrid | Vertical DE Pool Filter
- Effective Filtration Area = 48 sq ft
- Diatomaceous Earth Required = 6 pounds
- Height = 40.5 inches
- Public Design Flow Rate = 96 GPM
Hayward DE6020 ProGrid | Vertical DE Pool Filter
- Effective Filtration Area = 60 sq ft
- Diatomaceous Earth Required = 7.5 pounds
- Height = 46.5 inches
- Public Design Flow Rate = 120 GPM
Hayward DE7220 ProGrid | Vertical DE Pool Filter

- Effective Filtration Area = 72 sq ft
- Diatomaceous Earth Required = 9 pounds
- Height = 52.5 inches
- Public Design Flow Rate = 144 GPM
Summary of Differences in the Hayward ProGrid Series
A couple of these differences are obvious. They’re all different heights, but the gap between each one isn’t too big. You’ll also have to use a different amount of diatomaceous earth when you want to cover the grids so they’re ready to start collecting dirt and debris. The other big one is the flow rate, which will depend on the pool in your garden and you’ll be able to find this information out easily.
The one you might not be too sure about is the effective filtration area, so we’ll give you an explanation that is easy to understand. Imagine you’ve taken out all of the grids inside your pool filter and unrolled them so they’re lying flat on the ground. The EFA is the amount of space they would take up once this was done. Basically, more sq ft means it will last longer between backwashes.
Video | Pool DE FilterΒ β General Tips, Tricks & Troubleshooting
Which ProGrid DE Pool Filter Is Right For You?
You can check the flow rate of your pool, but we went in-depth about the Hayward DE4820 for a reason. It’s going to be capable of handling any in-ground swimming pool, even if it’s an extremely large residential one or a pool used for commercial purposes. One of the smaller pool filters could be enough for your swimming pool, but it’s always recommend to go a size or two bigger and the DE4820 sits directly in the middle of the series.
Cleaning Your Hayward DE4820 ProGrid Pool Filter
Earlier on we talked about backwashing, but unfortunately cleaning your Hayward DE4820 properly is a bit more time-consuming. Every so often you’ll need to get inside the unit to clean the grids properly. Once a year you should also take them apart and clean each grid one by one. Right now we’ll quickly discuss how you can clean the grid assembly as a whole, which can be broken down into the following two parts:
- Setting The Pool Filter Up
- Cleaning The Grid Assembly
β Setting The Pool Filter Up
It’s crucial you set everything up correctly for your own safety. You’ll be able to find the exact instructions inside the owner’s manual, but we’ll cover the basics today to show you the work required before you buy anything. The most important step is turning the power off at the pump, and to stay on the safe side it would be a good idea to do this at the breaker box to guarantee your safety.
You’ll then proceed to carry out a few small tasks around the unit. Open up the air relief valve so all the built up pressure can escape. Take the drain plug off to let all the water flow out of the pool filter. You’ll then have to take the clamp off using tools, and we’ve already touched on why it might be stuck. The upper section of your tank might need a little knock to loosen it up too.
The last part of the setting up process isn’t necessary, but if you’re not terribly strong it’s recommended. Take your hose and begin to wash the grids while they are still sitting in the tank. It will get some of the excess diatomaceous earth off to lighten the grid assembly. It’s also worth noting, some people do stop at this point because they feel the grids are clean enough.
β Cleaning The Grid Assembly
If you’ve decided you want to give the grid assembly a thorough clean you’ll need to lift it out of the tank. Place it on the ground somewhere you don’t mind the diatomaceous earth draining away. Once it’s in position you can get your hose and try to reach into as many places as possible. If you want to get the extremely fine particles off you should rub down the grids with a brush too.
Before you put the grid assembly back into the tank you can give the inside a proper scrub. All of the water should flow out of the drain hole. Pick the grid assembly up and place it into the tank in the same position you lifted it out. Now just go through the setup process backwards until everything is back to normal again. Cleaning the grids like this will extend their life so it’s worth doing.
Please Note: You’ll want the grids to be as clean as possible, but under no circumstances must you use a pressure washer. The amount of force hitting the grids will destroy them.
Video | Cleaning the Hayward DE4820 DE Filter ProGrid (and other models)
Common Mistakes People Make
There are some common mistakes lots of people make when they’re getting used to their new DE pool filter. No doubt you could fall victim to these too, so let’s quickly cover them so they’ll hopefully be ingrained in your mind:
Not Having Any Diatomaceous Earth β This one isn’t dangerous, but it’s certainly quite annoying. Before you backwash the system you’ll need to make sure you have enough diatomaceous earth stored away to replace the stuff you’re going to flush out. If it’s not there you’ll not be able to turn anything on until you take a trip to the store.
Only Tightening The Bolt By Hand β You need to remember there is going to be a lot of pressure inside your tank. It’s not going to stay in one piece for very long if you only tighten the bolt using your fingers. This is either done accidentally or on purpose because you didn’t know any better, but if you’d like the pool filter to remain intact always use the correct tool.
Leaving Your Air Relief Valve Closed β We mentioned this earlier on and it’s one of those things people forget to do. The air relief valve should be left open until nothing but water is spewing out. If you leave it closed and there is lots of trapped air inside the pool filter it will cause a lot of trouble you don’t need.
No Backwashing When The Pump Is On β When you’re going to backwash the system you’ll need to set a few things up first. The big one is turning the valve into the backwash position and locking it. This must not be done when the pump is still switched on. Everything won’t suddenly start working in reverse like some people think.
Video | Backwashing the Hayward DE4820 DE Filter ProGrid (and other models)
Operating The Filter Without DE β Not only should you use the correct amount of diatomaceous earth, but you should feed it into the system as fast as the plumbing will take it. Operating the filter for longer than a couple of minutes can cause damage to your grids and they won’t last long.
The Smart Choice For A Clean Swimming Pool
You never really know what is sitting in the water when you go for a swim. It’s hard to think about all the nasty things finding their way inside your mouth. The Hayward DE4820 ProGrid is certainly capable of putting a stop to it, because it really will collect more particles than all of the other models out there.
There is obviously a reason why it’s so popular with swimming pool owners. You only have to look at the things they’ve said about the pool filter on Amazon. It might be a good idea to read the reviews, because you know they’re unbiased and it’s much better taking advice from multiple sources before making a big purchase.
Visit the Hayward site to learn more about their expansive range of pool products.
Hayward C9002SEPΒ Β | D.E. Cartridge Filter Separation Tank

The Hayward C9002SEP is engineered to seamlessly integrate with vertical grid diatomaceous earth (DE) filters, with 80 square feet of filtration area. The Hayward ProGrid DE Separation tank is great for water conservation and functions by returning your chemically treated backwash water to the pool.
Features:
- Rugged, reusable polypropylene containment bag holds up to 10 lbs. of used D.E. filter powder
- Single locking knob for easy access
- Comes complete with 2″ FIP or 2″ SKT connections for full-flow performance
- Compliments both new and existing vertical grid D.E. filter installations
β View or download the MANUAL for the Hayward C9002SEP.