New IntelliPH

[Rsmith]

Most of the “hard” plastic components are going to be made of materials that have an excellent chemical rating for acids. The most susceptible part of the system will be the flexible tube in the peristaltic pump as there are not many materials that are both flexible AND resistant to concentrated acids.

Since concentrated MA is a hazard to surfaces and equipment, my suggestion from a process engineering standpoint is to simply keep spares of the pump tubing on hand and change them out regularly, once per season at least. Change them even if they don’t look like they need to be changed. The reason being is that it is cheaper to replace the tube then fix damage from an accidental leak caused by failed tubing. The hard tubing that runs to the injector can probably go for long periods of time between changes as would the injector check valve itself. The flexible tube in the pump is going to be your weakest link.

Thanks. My pool is only open for about 5 months a year and the first and last of those 5 I am manually chlorinating so really just 3 hard months of SWG and IntelliPH. It is my plan to replace the tubing and pump every offseason.

 

[Lake Placid]

Question. Do you dilute the acid that you put in the canister? I have been 1/1. Just wondering if it matters. I suppose the settings would have to be higher therefore working the dispenser harder than if it was straight acid?

I run full strength 31.45% muriatic. Allows me to dose at lower % settings (around 20% or less.) Stenner tube gets changed at startup every year.

 

[Dirk]

Do you dilute the acid that you put in the canister?

Yes. I buy 31% acid and dilute it 1:1 with water.

The manual says to dilute but doesn't specify what strength should be diluted.

I thought (and have mentioned here) the same thing. Another here replied that we are supposed to assume that Pentair is referring to 31% acid. I'm not sure why we're supposed to assume that, but that's the answer I got when I asked.

I mistakenly bought 14.5% acid last time. It was actually kind of nice to just dump it in without diluting.

This is probably what I should do, but the local 14% is almost as much as the 31% at my Lowes. Though I should probably check to see if that is still true, since all the price hikes.

my suggestion from a process engineering standpoint is to simply keep spares of the pump tubing on hand and change them out regularly,

Exactly what I started to do. You can buy them in pairs.

once per season at least

I neglectfully ignored the Pentair recommendation to do just that, and let mine go four years. That's'a no good. When I finally got around to changing it, it was badly corroded-looking and very stiff. I can't imagine the acid was dispensing at the proper rate. I agree, once a year is prudent, and that's what I'll be doing from now on, each spring.

The flexible tube in the pump is going to be your weakest link.

I have found that to be true.

The hard tubing that runs to the injector can probably go for long periods of time between changes as would the injector check valve itself.

That's mostly true. The tube should be fine (mine is, still using the original). I've disassembled my injector after four years and found that the components within the injector's body that are responsible for the "checking" were all looking like new. They're all hard plastic. Save two. There are two o-rings inside that were badly deteriorated. So Matt's analysis is dead on. The hard plastic stuff hold up, the soft pliable stuff succumbs to the acid. I replaced my injector after year four.

I will not likely replace my injector annually, but I did buy two, to keep one as a spare. If the o-rings leak, that can bring down your whole filtration system. So you can keep a PVC plug on hand, to cap off the threads that accept the injector, should you ever need to, or you can keep a spare injector on hand. I'm doing both.

Sidebar: The other reason to keep spares on hand, for everything you can reasonably afford, is because many of your pool components, if they fail, can bring down your pool's daily filtration. With today's supply chain issues, that can be a big deal. I just read that someone is going to have to wait months for a new pump. Now I can't afford to own two IntelliFlo pumps, but for the parts I can afford, especially those that are consumable anyway, it's prudent to stock up.

I disassembled my original injector to inspect it, because I wasn't sure if those need regular replacing or not. But it didn't go back together all that well, so I won't do that again. Instead, I will perform a simple, periodic test, probably once a season at first, and then more often as the thing gets older. With the filter pump on, but the IntellipH defeated*, so it won't inadvertently pump while performing this test, just unscrew the nut that is clamping the 1/4" acid feed tube to the injector, and carefully remove the acid tube from the injector (so as not to splash yourself with any acid that might be in the tube). If no water leaks out of the top of the injector, then the o-rings are working fine. If you see a leak, then the o-rings have failed. They're not really replaceable, as they are not typical o-rings, just buy a new injector at that point.

* To "defeat" the IntellipH, you can:
- run an automation circuit that doesn't power on the Intelliph/IntelliChlor combo, or,
- WITH THE BREAKER OFF, you can physically unplug the IntellipH from it's power supply (or from your automation controller if it's plugged into that), then restore the breakers and then turn on the filter pump, or
- you can run a manual dose cycle on the IntellipH, as it won't inject again after that for another 60 minutes.

Point being is to make sure the IntellipH doesn't start squirting acid all over you and your equipment while you have the 1/4" acid feed tube disconnected during the o-ring test.

 

[Dirk]

Did you snip off a short piece of the 1/4" tubing and it's just sort of hanging from the IntellipH vent? With its end very close to the IpH? Is that what I'm seeing in your pic?