The Pentair Clean and Clear Plus series is Pentair’s flagship line of cartridge swimming pool filters. It’s quite likely that you have one of these filter models filtering the water in your pool. Especially if you’ve acquired a new filter or even a new pool in the past 10 years or so, Pentair is often the go-to brand for pool builders and repair services alike.
Over the course of my career I have cleaned thousands cartridge pool filters, and it is true that all cartridge filters are pretty much the same technology. So regardless of your model, this article will help you keep your filter running smoothly.
Primarily, there are two types of cartridge filter styles in service. The four-way style which ranges in size from 300 square foot up to 500 square foot. Then there is the single cartridge style, ranging from as small as 50 square foot up to 250 square foot models. Our focus in this article is going to be the four-way models, which in Pentair’s case is the Clean and Clear Plus, 240, 320, 420, 500, and 520 square foot models.
Inspecting a Pentair Clean and Clear Plus Filter Before Tear Down and Cleaning
Before I go tearing into any filter, I like to take stock of what I’m working with. So let’s first point out all the parts as you approach the filter tank. A lot of folks like to go from top to bottom, but in this case I want to go from the bottom up.
Each of these units has a tank base which consists of the bottom tank of the filter canister. Near the bottom of the tank (under the plumbing for post 1998 models) there is a drain plug along with its O-ring. Moving up from there are the inlet and outlet bulkhead fittings that have the plumbing running through them with union style connections, along with each O-ring. Holding the two halves together is a metal clamp band with one barrel nut tension spring assembly, early models may have two barrel nut assemblies. Moving up from there you will have the tank lid or top half of the canister. Attached to the top of the tank lid is a pressure gauge assembly with a combined pressure relief valve.
It’s important to take a mental picture, or a literal picture, of the positioning of each of the movable parts prior to opening everything up, because if one thing is wrong dangerous things can take place.
What Are the Steps to Safely Open up the Filter Cartridge Tank?
Before servicing any piece of equipment, always ensure energized equipment, or potentially energized equipment is de-energized.
- Turn off all pumps and ensure they will remain turned off for the duration. I always anticipate the worst-case scenario that something will be broken, and I have to run to the store, so I turn everything off at the breakers in-case the timers decide to pop on unexpectedly.
- The next step is to dissipate the energy that is built up inside the tank by opening up the High Flow manual air relief valve at the top of the tank by turning it ¼ turn counter-clockwise. Air should be pulled into the tank thus draining water out of the tank. If water comes out instead, make sure all pumps are off, and if there are any valves to isolate the pool from the equipment they may need to be closed. If there is no movement one way or the other, you may need to open the drain plug at the bottom of the tank to drain out the water. ONLY do this if you are positive the tank is NOT under any pressure. Keep track of the O-ring!
Now that the pump and filter is de-energized, we are free to open up the filter safely.
Opening the Tank on a Pentair Clean and Clear Plus Pool Filter
The Pentair Clean and Clear Plus ranges from 240 square feet to 520 square feet. The only difference between the sizes is the height of the outside body which directly correlates with the length of the cartridges inside. So, splitting the tank on each will be exactly the same. While going through the filter, it’s a good idea to give everything a thorough inspection to make sure things are working right. Don’t worry, I’ll explain how.
- Barrel Nut and Tension Spring Assembly: you will need a 3/4-inch socket or wrench to loosen and completely remove the barrel nut and tension spring assembly. Make sure to take note of which washers are in what order.
- Band Clamp: Remove the band clamp from the circumference of the filter. Be careful, the clamp likes to jump off and fall.
- Tank Lid: Lift the lid up and over the top of the cartridges inside. Be cautious not to lift the tank top from the air bleeder and pressure gauge assembly as it can break quite easily. Once the lid is completely off set it to the side to be inspected and cleaned.
Now you will see the four cartridges that need to be cleaned. If this is your first time doing this, you may want to take a quick picture of how the assembly looks all put together. As you look everything over, the four cartridges should be vertical, the top manifold should be tight, and the center tube and breather screen should be intact.
You should see at the top of the four cartridges a large plastic manifold holding the four cartridges together. Attached to a white pipe running up the center will be an air breather screen. As the pump turns on this tube allows air to be automatically bled from the filter, the screen keeps stuff in the filter from finding its way back to the pool through the breather / bleeder tube.
- Breather / Bleeder Screen: Remove the breather screen which may be quickly rinsed off and replaced. Many times, these screens will get crushed, so you want to inspect it for its integrity. If its crushed beyond repair, these are relatively cheap and available at any pool supply house. Do not run the filter without one though.
- Top Filter Manifold: Next remove the top manifold. Sometimes these are stuck from being under pressure so you can just grab ahold of it and wiggle it from side to side breaking it loose from the four cartridges. Don’t worry, at this point there’s not much you can break, give it a good back and forth and pull the manifold straight off. Give the filter top manifold a quick inspection looking for any cracking or other Integrity issues. These are under a lot of pressure so often there will be signed that the plastic is starting to give out by odd-colored spots. Set it to the side to be replaced after the cartridges have been cleaned.
- Body O-ring: Remove the O-ring from around the circumference where the two halves of the cartridge canister come together. Inspect the O-ring for any cracks. If there are any cracks replace the O-ring. Always lubricate o rings with silicone or Teflon based lubricant before replacing it. Make sure the mating surfaces are clean as well.
- Filter Cartridges: One by one remove the cartridges by lifting straight out of the canister base. I always inspect the cartridges closely before cleaning them, because if they need to be replaced, why waste my time cleaning them. Check the end caps (both ends) for cracking or severe discoloration, or even separation from the center pipe or media. Inspect the bands around the media. Typically, if the bands are loose or broken, the cartridge needs to be replaced. Finally look at the paper media, if it appears the pleats are torn or not crisp, it’ time to replace. Generally, if the filter is serviced correctly at the right intervals, the cartridges should last 4 – 5 years in four-way cartridge filters.
- Cleaning the Cartridges; If the cartridges look good, soak them in a bucket of 20:1 water:muriatic-acid solution until the solution stops bubbling. I alternate them in while cleaning. Using a high-pressure nozzle attached to a garden hose, or a pressure washer, clean deeply into each pleat from top to bottom. The filter should get fairly close to being white. Clean the filters until the water that runs out runs clear. Another sign that it may be time to replace the cartridges is if they don’t get back to white as they may be embedded with a lot of debris.
Assembling the Cartridge Filter After Cleaning
Before just throwing everything back together, take a quick look at the bottom half of the filter tank body. If there is debris sitting in the bottom you may need to run some water through and rinse everything off. If you left the bottom drain off everything will just flush out. Lube up the O-ring and replace the drain plug.
Inspect the bottom manifold for and cracks or other fatigue. Give the tank a look over for the same concerns. If everything looks good, start reassembling the Pentair Clean and Clear Plus pool filter.
- Body O-ring: Make sure the body O-ring is lubricated and in position on the lower tank. This is much easier and cleaner to do when the cartridges are out of the filter.
- Replace Cartridges: Place each filter 1-4 on a corresponding spot on the bottom manifold. The cartridge should slide over the coupler and slightly snap when you press down firmly. When in position the 4 cartridges should stand vertically at the same height without falling over.
- Top Manifold: Put the top manifold over the top of the cartridges. You may need to orient it so the bleeder pipe aligns correctly. The manifold should need to be pressed down onto the four cartridges, if not then its upside-down. Press the manifold down firmly. The four cartridges should be more-or-less interconnected as one unit. Make sure the bleeder filter is on the center bleeder pipe.
Now the cartridges are all in place and the top tank is ready to go on. Before replacing the tank top make sure to inspect it for any damage or material fatigue. Clean the mating surface to avoid any leaks at the O-ring.
- Tank-Top: Replace the tank top over the top of the cartridge assembly. When placing it down onto the mating surface, try to do so evenly so as not to pinch or compress the O-ring or inadvertently push the O-ring off track. Close the air bleeder valves for a moment and rotate the lid so that the pressure valve is convenient to read. Make sure the bleeder valve is open.
- Band Clamp/barrel nut assembly: This part can be a little trick at times. Press down the tank top so that there is no gap between the two halves. Then quickly get the band clamp around the circumference of the joint. Start threading the barrel nut assembly into place. Usually, you can hand tighten this and then double-check everything is aligned. Once alignment is confirmed, I like to then use an impact gun with a ¾-inch socket attachment to tighten down the barrel nut. Once tight, use a rubber mallet to seat the band clamp, and then re-tighten the barrel nut assembly. Repeat as many times as is needed until the spring coils on the barrel nut assembly are touching and don’t loosen after hitting the band clamp with a mallet.
- Bleeding the tank: Not that you are sure everything is put back together correctly, open up any valves that you had to close before disassembly. Turn the breakers back on. MAKE SURE THE BLEEDER VALVE IS OPEN on the Clean and Clear Plus Cartridge Filter. Turn the main filter pump on and step back. SAFETY PRECAUTION: trapped air in a filter is very dangerous if anything malfunctions you don’t want to be near it when it happens. As air is pushed out of the filters air bleed valve you will hear it filling up. As soon as water shoots out close the valve.
Inspect the Filter Cleaning Job
Essentially the job is complete at this point. The system will still take a few minutes to work out any air left in the pipes and filter components. Take a look at the pool returns, there should be nothing shooting into the pool except clean water and maybe a few air bubbles. Go back and take a look at the Pentair Clean and Clear Plus Cartridge Filter, is there any water dribbling out from under the band clamp? If there is you need to disassemble the filter following the above-mentioned procedure to ensure the O-ring is seated properly and lubricated. Or it could be the band clamp wasn’t tight enough.
This job is relatively simple, but due to the safety complications, it can be dangerous, so please be careful. And when in doubt, hire a pro. Most pool service companies will charge only a small fee to clean a Pentair Clean and Clear Plus cartridge filter. Trust me, they won’t be getting rich off of that service call, but don’t be surprised if they try to upsell you. That’s their job.
Check out the next article to see The best test kits for Swimming Pool Owners
Check out the next article to see The best test kits for Swimming Pool Owners
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I have owned a swimming pool service and repair business based in the East San Francisco Bay Area in California for 10+ years. I have run into a great many scenarios. Repairs, replacements, maintenance, and service. I'm here to share the lessons I've learned over the years and hopefully help homeowners make informed decisions for the most expensive investment in their home.
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