Hayward ProGrid

The ProGrid is Hayward's vertical grid D.E. filter: a tall tank with a clamp around the middle, a valve on the side, and eight curved fabric grids inside. The grids get coated with diatomaceous earth, and the D.E. does the filtering. Hayward sells it in 36, 48, 60 and 72 square feet, all 24 inches wide, and the owner's manual still covers a 24.

The model number tells you the size: DE4820 is the 48. Add W3 in front and it is the same filter in Hayward's Open Line. Hayward lists the same specifications for both; what changes is the warranty.

Two flow ratings, and a ceiling

Hayward's performance chart gives each size two design flow rates:

• Public, 2 GPM per square foot. Hayward calls this the maximum allowable NSF rating: 72 GPM on the DE3620, 96 on the 48, 120 on the 60 and 144 on the 72. It is also the figure in the owner's manual and on the sell sheet.
• Residential, 2.5 GPM per square foot. 90, 120 and 150 GPM on the 36, 48 and 60.

The DE7220 is the exception. By the rule it would be 180 GPM residential, but the chart stops it at 150, and the sell sheet says Hayward doesn't recommend more than 150 GPM through a ProGrid at all. The same sheet recommends 2-inch pipe for flow at 90 GPM or more, and gives the range as pumps from ½ to 3 HP.

If your pump's real flow sits between the two numbers for a size, the public figure is the conservative one to size by. Pump flow and filter area are worked through in the sizing guide.

How much D.E. it takes

Hayward's figure is 0.125 lb per square foot, so each size takes:

• DE3620 — 4.5 lb
• DE4820 — 6.0 lb
• DE6020 — 7.5 lb
• DE7220 — 9.0 lb
• DE2420 — 3.0 lb

That is more than Pentair asks. The FNS Plus takes 0.1 lb per square foot, so a 48 square foot Pentair gets 4.8 lb where a 48 square foot Hayward gets 6. Use the number for the tank you own. It is also printed on the filter's label.

With the pump running and fully primed, add the D.E. through the skimmer. Then read the gauge. That reading is your pre-coat pressure, the clean number everything else is measured against. The gauge in Hayward's manual has a green arrow and a red one: set the green arrow at the pre-coat reading.

One rule protects the grids: don't run the filter for more than a minute or two without D.E. in it. Pentair allows three minutes on its filter; Hayward's is the stricter number.

Backwash at 8 to 10 psi, then recharge

When the gauge climbs 8 to 10 psi above the pre-coat pressure, or reaches the red arrow, it is time to backwash. On a new or very dirty pool, the manual says to expect more frequent backwashing at first.

The valve isn't included, and the steps depend on which one you fit. With Hayward's six-position VariFlo:

1. Pump off. Set the valve to Backwash.
2. Pump on for about two minutes, or until the waste line runs clean.
3. Pump off, valve to Rinse, and run for 20 seconds.
4. Pump off, valve back to Filter.
5. Add a fresh charge of D.E.

The four-position SelectaFlo skips the rinse. The two-position slide valve backwashes with the handle up and filters with it down. On every one of them, the pump goes off before the valve moves.

Two details from Hayward's knowledge base are worth knowing. A good backwash removes only about 80 to 90 percent of the D.E., and the rest can stay clumped in the corners or caked in the middle of the tank. The manual still says to add the full amount afterward. But if D.E. shows up in the pool after a recharge, Hayward says to vacuum it to waste once it settles, and use a pound less after the next backwash. Taking the filter apart is the only way to get all the old D.E. out, and after that the full charge goes back in.

The manual also suggests Rinse, which sends water to waste, as the position to pre-coat in if a large cloud of D.E. comes back to the pool while you are adding it. Where D.E. backwash water can go is a local rule, and some areas restrict it. Check before you plumb a waste line.

When D.E. ends up back in the pool

Hayward's knowledge base narrows it to four causes on a vertical grid filter:

1. Too much D.E.
2. A tear in a grid's fabric
3. A crack in the top manifold
4. A bad o-ring on the standpipe, the pipe the grid cluster sits on

The first costs nothing to fix. The other three mean opening the filter, and all three parts are listed below.

When pressure climbs fast after a backwash

Hayward's knowledge base points at the grids. Minerals and oils embed in the fabric and shrink the area that actually filters. Hayward also says that too little D.E. at pre-coat lets debris lodge in the fabric the same way. Its fix is to clean the grids once a year, or once a season, with a degreaser and an acid bath if needed. If cleaning does not bring them back, replace them. Neither Hayward nor Pentair puts a number of years on a grid.

Before blaming the filter, Hayward's list for short filter cycles starts with the water: check for algae and superchlorinate if needed, and bring chlorine and pH into range. For low flow it starts with the skimmer and pump baskets, restrictions in the lines, and air leaks on the suction side.

Opening it up

Backwash first, then follow the manual's order:

• Pumps and power off, valves closed to the filter, and the air relief valve open.
• Take out the drain plug and let the tank empty.
• Remove the clamp nut and bolt with ¾ in. wrenches, spread the clamp ends and lift the clamp over the top. Don't drop it, and don't strike it with a hammer or metal tools.
• Lift off the upper body. Never lift it by the pressure gauge.
• Hose down the grids while they are still in the tank, with the drain open, to flush out the loose D.E. Hayward recommends its EC2024 cleaning wand for this.
• Rock the cluster gently to free the manifold from the outlet elbow, then lift it straight up by the handles.
• Wash the grids inside and out with a garden hose and brush off the fine particles. Do not pressure wash, which damages the cluster.

Putting it back together

This is where the ProGrid differs most from other filters.

• Lubricate the outlet elbow o-rings with Jack's Formula 327, and seat the manifold outlet over them.
• Do not lubricate the metal reinforced seal. Wipe both seal surfaces with a clean cloth and no solvent. Hayward says never to clean any filter part with a petroleum solvent.
• Center the upper body on the seal with the labels visible, and press it down evenly.
• Fit the clamp with its ends beside the labels, and put the nut on with its rounded end toward the clamp.
• Torque the bolt and nut to 150 inch-pounds with a torque wrench and a ¾ in. socket. Never rely on hand tightening.

150 inch-pounds is 12.5 foot-pounds. Many torque wrenches read in foot-pounds, and setting one to 150 would be twelve times the figure. Pentair's FNS Plus clamp is 16 to 18 foot-pounds, so don't carry a number over from one filter to the other.

Hayward is emphatic about the clamp for a reason. Its component separation warning says system pressure can cause explosive separation of the upper filter body, and it names three parts that must be genuine: the DEX2421JKIT clamp, the DEX2421J2 bolt and nut, and the DEX2422Z2 seal.

Starting it safely

1. Check the clamp is torqued, and that the air relief valve is in the LOCK position.
2. Put the drain plug in, with its o-ring.
3. Open the valves so water can go from the pool to the filter and back.
4. Open the air relief valve.
5. Start the pump without standing over or near the filter.
6. Close the air relief valve only once a steady stream of water, not air or a mix, is coming out.

If water appears at the clamp, turn off the pumps and the power immediately. Stay away from the filter until the water stops, then reassemble the clamp.

The air relief valve can be removed and refitted, but Hayward's manual reserves that job for qualified pool professionals.

Winterizing

Where freezing is expected, drain the filter, take it apart and clean or replace the grids, and reassemble it. Then leave the drain plug out for the whole winter, so trapped water cannot crack the filter body.

Check the prefix before you buy

• DE4820, from a dealer: Expert Line, three years parts and one year field labor. A Hayward Rewards dealer can extend that to three years of both.
• W3DE4820, Hayward's Open Line: one year parts, no labor, wherever you buy it and whoever installs it.

On both, grids and o-rings are wear items and are covered only for manufacturing defects. On a D.E. filter those are most of what wears out, so the headline term matters less than it looks. Replacement parts bought later carry their own shorter terms. Hayward's part pages for the ProGrid list six months. The Hayward brand page explains the two lines.

Against the Pentair FNS Plus

• D.E. — 0.125 lb per square foot against Pentair's 0.1.
• Backwash trigger — 8 to 10 psi over pre-coat against Pentair's "about 10".
• Running dry — a minute or two against Pentair's 3 minutes.
• Clamp — a bolt at 150 inch-pounds against a cast clamp at 16 to 18 foot-pounds.
• Flow — the same two rates, 2 and 2.5 GPM per square foot.
• Sizes — 36 to 72 square feet against Pentair's 24 to 60.
• Warranty — three years parts and one year labor from a dealer, against Pentair's two years parts and labor. Bought online, both drop to one year parts only.
• Fineness — Hayward's knowledge base says D.E. filters catch particles down to 1 to 3 microns. Pentair's FNS Plus brochure says particles as small as 5. Neither describes a test, so treat both as claims.

Where Hayward's documents disagree, or are unclear

• How many grids. Hayward's product pages list 10 filter elements. The manual and the sell sheet both give eight: seven full and one short.
• Heights. The manual gives 34.1, 40.1, 46.1 and 52.0 inches for the 36 through 72. The sell sheet and product pages give 34.5, 40.5, 46.5 and 52.5. The manual's metric figure for the DE6020, 107 cm, doesn't match its own 46.1 inches.
• The filter bodies. The current manual lists the upper bodies as DEX2420BT to DEX7220BT and the lower body as DEX2420AT. Hayward's site sells the filter head and body with the clamp, DEX4820BTC and DEX2420ATC, which are the numbers in the earlier manual.
• The seal's number. The manual's text and parts table say DEX2422Z2. Its own figure labels the seal DE2422Z2.
• The slide valve. The earlier manual prints SP0410X5025. The current manual, the sell sheet and Hayward's parts listing all give SP0410X502S.
• The slide valve's handle during recharge. The manual has you set it to Filter, down, then add D.E. "(Handle in Up position)". Hayward's knowledge base says handle down, then add the D.E. Down is the Filter position.
• How fast to add D.E. The manual says as fast as the plumbing will take it. The knowledge base says to add it slowly.
• The rinse. The manual gives 20 seconds. The knowledge base gives 20 to 30.
• The pressure gauge. The product pages say no gauge is included. The manual lists gauge ECX2712B1 and has you fit it if it is not already installed.
• Winterizing. The current manual's steps mention cleaning the "filter cartridges elements" and point to a "Removing Cartridges" section it does not have. It means the grid cluster.
• A copied notice. The current manual's installer notice calls the product a variable speed pump.
• Who extends the warranty. The sell sheet credits the longer term to a Totally Hayward partner, the product pages to a Hayward Rewards partner. Hayward's warranty page names Hayward Rewards.

The DE2420

The 24 square foot model appears in both manuals, with its own cluster, outlet elbow and an element spacer no other size uses. It is not on Hayward's filter listing or the 2023 sell sheet, but its parts are still sold. If you have one, the parts table below covers it.