Pentair Intelliph - Further Reading

Basic Operation

Pentair IntellipH

The IntellipH dispenses a set amount of acid every 60 minutes while the filter pump runs. It does not measure the pH or determine how much acid is needed. Over time, the user is expected to dial in the amount of acid required each hour.

If wired correctly, the ipH can't pump while the filter pump is off, just as the IC40 can't produce. And the ipH doesn't dispense while the IC40 is producing, the ipH controller turns off the IC40 just before it dispenses.

The ipH controller monitors the IC40 flow switch and won't dispense without flow (or isn't supposed to).

When acid is dispensed, the ipH controller stops the IntelliChlor ICXX chlorine generation during the IntellipH acid dispensing. The cell output is set to 0 with no LEDs lit and the Cell Status LED is off.

Checking the tank contents should be a daily chore, along with spot-checking the filter gauge, the leaf baskets, the water level, etc. The problem with automation is that it will eventually fail, so you need to treat every day as the day it might happen.

The IntellipH Controller requires the IntelliChlor Power Center and ICXX cell to be used with it. There are several reasons Pentair made the IntellipH dependent on an IntelliChlor:

• They use the same power supply
• That power supply is supposed to be wired only to run when the main pump is running
• The IpH monitors the IC's flow switch so that it won't pump acid unless there is flow past its injector, independent of the pump getting power or not
• The IpH monitors the IC's temperature sensor so that it won't pump acid unless the water is warm enough
• The IpH disengages the IC while pumping acid so that you don't get high concentrations of acid and chlorine in the plumbing simultaneously (which can be dangerous).

That all provides safeguards against allowing the acid pump to inject acid if the pump is not running or if there is no water flow for other reasons. If the IntellipH tank and pump are used with a different controller, these safeguards should be implemented.

Pentair Sanitizer & Water Quality Catalog 2025-2026

Pentair Sanitizer & Water Quality Parts Catalog 2025-2026

IntellipH Spa Mode

The IntellipH will enter SPA mode anytime the ICXX cell is set to less than 5% output.

To take the IntellppH out of SPA mode, raise the ICXX generation percentage by 5% or more.

IntellipH Communication with IntelliChlor Cell

The IntellipH, IntelliChlor, EasyTouch, or IntelliCenter use the RS-485 data comm lines to communicate. RS485 is not necessarily a link. There is no negotiation between the master and slave devices on the bus.

A relay in the IntellipH switches the yellow/green comm wires. When IPh is dosing, it responds to EasyTouch requests as a dummy cell and sends requests for 0% production to the cell. Then, when it completes, it switches back to allowing EasyTouch messages to make it to the cell.

If the cell does not respond, there is a COMM LINK ERROR. The automation system simply keeps track of whether the cell responds OK to the command that disables the control panel. When dosing IPh, it responds to EasyTouch, and when it is not dosing, the IntelliChlor cell is supposed to respond. If that request never makes it to the cell, there will be no response, and a COMM LINK ERROR will show up.

You can try to change the settings at the IntelliChlor cell if it is in this Comm Link error state. This will tell you if the IntelliChlor still receives messages from EasyTouch or IPh to turn off the control panel. If any of the buttons respond on the cell it is not getting messages from the EasyTouch or IPh. If you can make any changes on the cell, then the requests are not getting through from either one. NOTE: It takes 30 seconds or so for the cell to give up the panel lock, depending on where it hits the polling cycle.

IntellipH with IntelliChlor IC60 cell

A members' board on his IntelliPH fried for the second time in about a year. The warranty service company told him that Pentair says the IC60 pulls too much current for the IntelliPH, and Pentair wants to swap out the IC60 for an IC40.

If you plan on this equipment combination, you should check with Pentair regarding their latest thinking.

Two Different Peristaltic Pumps

522474 Pump

I have determined that the replacement peristaltic pump is indeed the old circa 2014 Shurflo pump. I requested Pentair get me the new, correct Stenner pump. I think the reason I ended up with the old one circa 2014 is that there is not a part number for the entire Stenner motor and pump head, but there is for the circa 2014.

There are two types of tank-mounted pumps:

• black and white square pump 521348Z (old part, cheap) ShurFlo pump
• blue cover semi-round pump 522474 (new pump) Stenner pump

Maintenance & Repair

The old pump had to be entirely replaced, the new blue pump can be repaired, and you're expected to change out the white tube every year.

You can order the super expensive Pentair parts for replacement, but it's a standard Stenner econ pump head that Pentair customized for their needs. So you can just order Stenner econ replacement parts for not just the white roller tube but the rollers as well. They are the exact same part, just a fraction of the price.

Also, Pentair only sells you the tube two-pack or a rebuild kit with one tube and the rollers for about $80. You can buy the Stenner econ pump head roller alone (EC350; make sure you get the "white" version instead of the "black" version) for a fraction of the price ($15).

Capacity of the Pentair 4 Gallon Acid Container

The TOTAL capacity of the Pentair Acid Container (521378) or (522472) is 4 Gallons (15.1 Liters). Adding 4 gallons to an empty container will bring the level of liquid in the container to the very middle of the protective grid or the bottom of the container's top mounting lip.

​However, of the 4-gallon capacity, 10 ounces (295.7 mL) of liquid at the bottom of the canister is unusable. This is because the suction tube and plastic filter screen do not quite go all the way down to the bottom of the container. Hence, the “usable” amount of liquid in the canister is 3 Gallons, six fluid ounces (3.375 gallons), or 11.8 Liters.​

Based on these measurements, it was also determined that the vertical sticker placed on the side of the container is inaccurate in representing actual liquid increments within the container.​

On page 1 of the IntellipH Acid Dispenser System Installation and Users Guide, the “Storage Canister” is listed as “3-1/2 Gallons.” This stated value in the user guide is off by only 2 ounces. Still, I’m just saying that in typical Pentair fashion, information found in Pentair documentation is NOT always accurate and, in many cases, incomplete.​

Note: we assume the same numbers defined above also apply to the Pentair 4-gallon Chlorine Container (521397.) The only difference that could be found between those two part numbers (tank only), or between the two part numbers with a mounted pump (522472 vs 522473), is the fact that the color-coded stickers placed on top of the lids are different.

Pentair IntellipH Annual Maintenance

There are several things you can do and should do (in terms of annual maintenance).

You need to change the pump tube regularly. I think Pentair recommends it annually. You might be able to skip a year, but I wouldn't go any more than that. If it has turned brown or is stiff, it's done. While you might get acid out of the tube while it's disconnected from the injector, that doesn't necessarily mean there is a strong enough pump action to overcome the injector and the pressure in the pool plumbing.

There are parts in the injector that might be getting clogged up. It's possible to disassemble it, but it might not go back together all that well. Mine didn't. And while replaceable parts are inside the injector, I doubt you can find them anywhere. Pentair doesn't sell them. Just replace the injector; they're available on Amazon or Pentair. If that doesn't solve your problem, it's not money wasted, because if you don't need a new one now, you will eventually. Keeping an extra "in stock" is prudent. I replaced mine and bought two, so I have a spare. Given today's supply chain issues and ever-rising costs, buying an extra is just good planning.

While looking at the IPH from the side the pump is on, two fittings come out of the tank. The one on the left feeds the pump, and the other is a vent. Did you connect that to anything?

If not, you should. Here's why - The acid tank is supposed to be airtight. So, as acid is drawn from the tank, you need air to enter the tank to displace the acid leaving it. The same goes for temperature changes throughout the day and night: as the air in the tank heats and cools, the tank needs to breathe. And that air coming and going is provided by the vent. The problem is that as the tank expels air, it's also expelling acid fumes, which can chew up any metal near the tank. The corrosion often seen on those screws is likely from acid fumes. But they won't stop there; those fumes can and will attack any other metal nearby, even stainless steel, like your other pool gear, window frames, fence hardware, etc.

The solution is two-fold:

• Check the large o-ring of the IpH tank lid. Be sure it has no nicks or cracks, and give it a good coating of o-ring lube (the same stuff you use on your pump's lid o-ring or your cartridge filter's o-ring if you have one of those.
• Get yourself some 1/4" acid-resistant tubing (that should have come with the IpH). You can use the same tubing the IpH provided to attach the IpH pump to the injector if there is any left or grab some from online or at a big-box store. Then, you connect that tube to the IpH vent and run it as far away from the IpH, your pad, and any other metal as you can get. Try to slope it down from the IpH, then turn its end down, too. It'll still pass air, but the idea is to allow condensation to drain out, and pointing the end down will keep it from filling with sprinkler water or rain.

Lastly, Pentair recommends diluting the acid in the tank. You can cut 31% acid in half, adding 1-to-1 water and acid, or you can just buy the 14% acid. That helps minimize corrosion and helps with the longevity of all the parts susceptible to acid. If you're running 31% acid in the tank, that's asking for trouble.

Plus, if your IpH goes haywire and pumps the entire tank's contents into your pool, a diluted mixture won't cause as much havoc to your pool or swimmers, so it's an additional safeguard not to use full-strength acid in the tank.

Pentair IntellipH Parts

IntelliPh parts you may need during maintenance are:

• Pentair Injection Check Valve 522513Z
• Pentair Pump Head Tube Repl, Pent IntellipH,Stennenr Blue Pump, 2 Pk | 522480
• Pentair Intelliph Pump Repair Kit, 522386, if you need the wheel and tubes
• Pentair 522384 Tubing for IntellipH Controllers Chemical Injection

Stick to Pentair parts for the injector and pump components (shop for the best price), though there may be third-party stuff if you want to play the dice and save some money. The 1/4" acid tube doesn't need to be Pentair; you should be able to find that much cheaper. Just be sure it's made of a material that can withstand Muriatic acid.

There are a few models of IntellipH pumps floating around. If you have a newer IpH, the above parts are probably the right ones. But be sure to deal with a supplier that will accept returns should you order the wrong part.

Pentair IntellipH Schematic

Below is a schematic of the IntellipH board reverse engineered by member Ogdento. Ogdento (Tom) has been analyzing failed Intelliph board and identifying the components.

He noticed that were not only the comm chip (U5), protection diodes (D3, D4), and relay (RL1) blown but also transistor Q5, which switches power from the primary voltage regulator (U1) to the secondary voltage regulator (U2). U1 works fine and outputs ~11volts, but U2 was also blown. It doesn't regulate anymore.

U2 is supposed to generate 5 volts for the PIC microcontroller (U3), but he does not know how the microcontroller still works! U2 spits out the input voltage (minus a small drop). This is bad because the PIC microcontroller expects 5v, but U2 outputted around 10.

Problems

Intelliph Emptied Entire Tank of Acid

The warranty company for Pentair came out, and they replaced the entire peristaltic pump on my Intelliph with a different pump. Now the peristaltic pump says Shurflow, and it has four screws, not a lever, to replace the surgical tubing and/or the wheel. The Shurflow wheel appears to have only two rollers, not three like the original.

It sounds like they put on the older pump head. The newer one is a Stenner style; the Shurflo was the original.

Intellichlor ICXX Not Running

There was an issue where the ICs were having trouble running when connected to the intelliph. It seems these issues haven't been entirely resolved.

The IntelliChlor IC40 or IC60 cell can draw too much power through the IpH and burn out a connector. This thread describes a fix to the burnt connector.

Power Supply Connector Burnt Pin

A member had the connector from the power supply to the IntelliPh circuit board overheat and melt. He had this occur not only on the original unit but a replacement (complete new unit). He also replaced one control unit separately. The overheated pin in the plug occurs on the black wire only.

He replaced the connector with one from TE.com. The part number for the plug is 770759-1 (08P MINI UMNL PLUD HSG), and the part number for the pin socket is 1-794407-0 ( MINI UMNL SOK 20-16 AWG AU LF). They also showed the connector for the circuit board; however, he did not need that as he had purchased a new board. He also got a crimper from Amazon (Dupont Crimping Tool Qibaok Pin Ratcheting Crimper).

Hacking IntellipH to work in cold water

As IntellipH (IpH) owners know, the IpH depends on an IntellliChlor (IC). The IpH uses the IC's power supply and monitors its flow switch so that it won't dispense acid if the IC is reporting low flow. Unfortunately, it also monitors the IC's water temperature reading and won't dispense acid if the IC reports cold water. A fix for that is described in Hacking IntellipH to work in cold water.

Servicing an IntellipH Injector

Short version: ya don't! You replace it periodically.

Periodically—maybe a few times a year —perform a very simple, noninvasive test of the injector. Unscrew the white nut that clamps the acid delivery tube to the injector body and pull the tube out. Then, turn on the filter pump (relatively high RPM) and observe. If no pool water drips out of the top of the injector, then the seals are fine. If you see water, it's time for a new injector.

Test your IpH injector once in a while, as described above, and replace it as necessary.

See the thread for the whole discussion --> Servicing an IntellipH Injector

Tips

Adding a whole jug of Acid to the IntellipH Canister

Take a utility knife to the pad and unscrew the cap to the jug. Leave the seal on the jug and invert it into the canister. Then, bump the top of the jug, and it will break the seal. Then, take that utility knife and poke a hole in the top. About 5 seconds later, you can pull the empty jug from the canister.

Dilute 31% acid 1:1 with water

This means there's never more than 1.5 gallons of acid in the tank at any given point. Not enough to be much of a concern should the system malfunction.

Muriatic acid and water mix well; the mixture is almost complete when you close the bottle. HCl has an enormous solubility in water and, unlike sulfuric acid, is not very viscous, so it mixes well. If you add your jug of water to the IpH (yes, add that first) and then your jug of acid to the IpH, you can stick a plastic rod into it, give it three turns of your hand, and then close up the holding tank. By the time you clean up all your tools and take a sip of beer, the solution is mixed.