Stenner Econ LD for MA

[AllenA]

Hey Scotts,
Ok, also good to know. Long term reliability of the potentiometer / repeatability of the setting.
My rates will be way lower as mentioned above and probably won't do anything at all. But, do you by any chance believe that you need to clean it less frequently with your rate of diluted 1 oz / min? This may not be helpful to me but maybe others that would use the same "higher" flow rate. And, how long have you had this setup for?
Allen

 

[AllenA]

EDIT: so my internet went down and after refreshing several times I could not see my above reply. Once I posted this one, the one above show up. So this is a duplicate of the above.

Thanks Scott for the info. I'll keep that in mind. Basically it means that we can never assume that always still need to monitor, which was anyway in the plan since things change anyway.
As for the pre-SWCG setup, how long have you had it this way and do you believe that you don't need to clean the cell as frequently as others with the IC40?

 

[scottts]

The pool was done in October of last year, so about 7 months or so. I've run -.2 to -.3 LSI the entire time, pH 7.6. I've looked at the cell a few times but have never seen anything that needed cleaning so far. No calcium deposits. CH started at about 300 and is up to 450 now.

 

[AllenA]

Hmmm, how did you run the SWCG last winter? Frequency / percentage? I'm not sure if we can draw any hard conclusions based on winter's low CL demands which in turn would not raise PH that scale out the cell. My previous cell did not require any cleaning in winter also with minimal PH monitoring. It would be more interesting to find out what happens during summer. Did the PB push for this setup based on some previous experience / information he is aware of?

It if were to be contributing to keeping it clean, 2 potentials in my mind:
- The MA injections themselves being so close to the cell gently keep it clean as they raise the concentration of the MA ever so gently but enough to keep scale off the cell. Each alone are negligible but on the long haul, the effects are there. Exactly what everyone would want.
- Or, the controlled PH itself (which is often neglected by many of us) keeps the cell cleaner longer

But in the latter case, it also means that it would work just as well if the injections were to be after the SWCG.

I wonder if anyone else has such a setup with a longer install period that can help provide more insight into their experience.

 

[scottts]

Yeah, during the winter I was experimenting a lot with trying to get the intellichem control to work using ORP as the proxy for FC and dosing the IC-40 i response. I used the heat pump to keep the water stable at around 58F, the pH at 7.6. So, I don't have any consistent set of operational parameters for that time period.

While the pool was being built I really didn't learn enough to engage with them about how the system should have been installed so its just the way they did it and there are some things I now wish were different.

I agree that the cell may just stay clean because the pH is never out of wack, the LSI is always just slightly negative and I can adapt to chem and water changes really easily. For example CH has risen to 450 and the temp from 58F to 85F. I just bumped down pH to 7.5 yesterday to get a slightly positive LSI back to slight negative.

Really looking forward to this summer to see how it all plays under real stress.

 

[jonpcar]

Hey Allen, I think you made a good choice that gives you options. So I looked closely at the intellipH pointed out by @RDspaguy and being discussed over on this thread:

Stenner Pump Controller/Automation

Does anybody recall seeing any threads regarding the automation of a stenner pump (Acid or Chlorine)? I think that I have seen some here in the past but I have been searching for a while now and no joy. Looks like my dumb IntellipH, listens on the bus (according to some conversations that I saw...

www.troublefreepool.com

Allen, it turns out that this device does spread out the acid OVER the time the pump is running similar to what you are doing (but only in the first minute of each hour of pump run...haha). It does have a scaling factor that can be adjusted (your dial). Overall, it is a timer/pump active driven acid injection system very similar to yours.

But there is a caveat...apparently Pentair's intellipH only injects acid when chlorine is NOT being generated by the SWG. Personally I have always wondered about this...everyone knows your not supposed to mix acid and chlorine (apparently NOT mustard gas but something still dangerous). But I have never seen this talked about by Stenner acid pump guys who have SWGs. I have probably just missed these discussions.

Is that a real concern? The Pentair intelliph device does dose pretty quickly: 4oz/minute...that rate is always the same but it doesn't run for a full minute depending on your percentage run time dialed in.

 

[AllenA]

Scott's, it's good to hear that the setup is working good. Would love to hear how summer goes. I'll also come back once I have some data.

Jonpcar, interesting find. And also good to know about not mixing MA and CL. I may have known about it when I first researched 9 years ago but just forgot about it.

Btw, I started a new thread about controlling the pump with a flow switch here if you guys have any advice?

Flow Switch to control Outlet

Hi All, I want to prevent my Stenner pump (for MA) from ever running when there is no flow. I read this thread but I want to do it differently if possible and hopefully simpler. https://www.troublefreepool.com/threads/controlling-stenner-with-a-flow-switch.172656/ I am thinking of using a...

www.troublefreepool.com

Thanks again for your support! I really appreciate it.

 

[AllenA]

Finally all I need is here. I'll let you guys know how it goes.

 

[AllenA]

Installation was easy. I had the right tap to thread the pipe. I did put the injection point before the cell. 15 Gal tank bought online mixed half half. I think it's gonna take about 1 hour at full speed before the liquid reaches the injection point. Once it reaches I'll set it at half speed. I'll measure in a few days and adjust until I find this week's demand (pump's setting). Then measure once per week and dial up or down accordingly. Won't know or really care about the exact amount itself.

I'll fix the tubes nicely later on and will also install a tarp over the whole area to further protect from the sun. The motor is practically inaudible. It seems that it generates very (and I mean very) low warmth by itself (already evening) by touching the casing. The Circupool controller next to it is much hotter to the touch. We'll see tomorrow in the heat.

 

[jonpcar]

Darn...should have mentioned this. You (eventually) want the black tubing for UV protection if you get sun on your setup. The clear tubing will degrade in the sun...depending on how much you get, as soon as 4-6 months. Otherwise, looks good! An hour??? that is crazy slow...

 

[AllenA]

Ah, all those tubes choices so confusing. I don't get much sun in this spot anyway. Maybe 1 -2 hours per as it is between my house and neighbor. And with a white tarp on top it should be fine. But I'll keep an eye on the tube and if it fails I'll get a black instead. Thanks for the tip.

As for speed, on top setting the liquid was moving about 1/16 th inch per second. I think it took 45 minutes for the 15 feet total that I laid before and after. And now that I just calculated, it sorta matches. 15 feet x 12 inches x 16 steps per inch = 2,880 steps total. Divided by 60 = 48 min.

 

[spoonman]

I live in PHX also and have been dosing MA with an Econ T for about 2 years. I have the 15 gal Stenner tank with pump mount and simply keep a Weber bbq grill cover over the unit and have had no problems with heat, degradation, or fuming.

FWIW you can easily change the daily run rate on an Econ T. It is slightly easier to add time (than subtract) so it is a bit easier stepping up supply than stepping down.

I initially thought I would buy 34% also then attempt to mix. I quickly found that this was too dangerous to warrant the extra couple of bucks every few months. Pre-mixing was not worth it to me. I could probably run straight 34% but haven’t tried.

 

[AllenA]

Hey spoonman! Cool to see so many others from the area chiming in.
So, as I started to reply, I figured I would go check up on it. The sun is straight up and direct right now as part of my few hours per day direct sunlight on the equipment pad. It is currently 79F. The casing is in fact super hot now, much hotter than 79F to the touch. I just strapped a temp cover over it with some spacing in between (white foam from the salt cell packaging) to keep it from over heating. The foam should be a good insulator. I'll check in a few hours if that cools it off a bit. Wish I had one of those infrared Thermometers to get something more accurate but I'll rely on my touch for now.

I would have thought that if you use an Econ T, you would only run it during the night? Why would run it during the day?

As for MA, I've always used the 34% and never felt too worried about it. Maybe I should be... The pour into the tank went fine with a few minor spills (total of less than 1 oz) that I washed off at the end. One annoying thing that happens to me often is that the seal of the jug always deteriorates by the time that I use the MA since I buy usually in advance. Then it is not so easy to remove that seal anymore. Anything left over in the rim makes the pour no so fluid. Dumping straight into the pool was no big deal since I used to just flip over and walk around the edge of the pool. But now that I have to be precise, it is more important. However, from now on, I will still buy in bulk (say 3 two Gal boxes) but I will be adding them to the tank almost right away so that seal should not be as deteriorated as usual and I should be able to remove it cleanly in 1 go and have a cleaner pour. I could use a funnel to help but it would be best to use a large funnel. Don't want to wait over the acid smell for too long and can't risk not holding it.

 

[AllenA]

So here it is hiding and as cool to the touch as last night. The sun is no longer direct either by now.

 

[spoonman]

I have the Econ T scheduled for about 40 minutes around 8am. I chose this time as I never use the pool in the morning (not that it would much matter), it is the time I run my pump on high, and I don’t like running my pump at night due to noise. Plus, if anything ever happens I have all day to notice if there is a visible problem.

Very true about the acid seals. The broken seals cause glugging issues. IMO they come straight from the store that way so probably won’t make much difference how quickly you use.

Sometimes people dilute the 34% (I just buy 17%) but it is tedious (and somewhat dangerous) because the acid and water have to be blended before entering the tank. Reason is that acid must only be added to water, not the other way around. Since the Stenner tank always has some acid left in the bottom, I can’t just start adding 1 part water, then 1 part acid. I’d have to pre blend in a separate container. Too much trouble IMO.

 

[AllenA]

Ah, ok, makes sense.

 

[AllenA]

So an update after a couple of weeks. Everything works perfectly. Tested earlier and got 0.05 A current draw with a good multimeter. Nice and slow constant 24/7 injection. The make shift foam is still there for now and the unit is barely warm at full sun so no overheating issues. These days it's about 100 F outside. I adjust slightly the dial as I fine tune to my PH goals. I would recommend this pump for its ease of use. Also note that I added a flow switch directly on the outlet where the pump is plugged. I described it in another thread mentioned earlier if you want to know the details.

 

[jonpcar]

Congrats trailblazer Allen ! Turned out to be a nice plan for you...not too many people run their pool pumps 24/7 but I think the number is growing and your unique Stenner pump might be a good option for them. Of course it would work for lower runtimes as well...but for calculation purposes it probably would be best if a SET number of hours of pool pump run time (per day) is used throughout the year, and also afairly long pool pump run time” because of the slow injection rate of that particular Stenner pump family.

Nice solution and looks like the wattage is much less than I anticipated as compared to the more standard Stenner pumps like mine. Keep us updated...

@spoonman, I don’t dilute my acid, but I was unaware of the -recommendation- that dilution of acid should be accomplished by adding the acid to water and not vice verse...nice to know. Is that for splashing purposes?

 

[spoonman]

Congrats trailblazer Allen ! Turned out to be a nice plan for you...not too many people run their pool pumps 24/7 but I think the number is growing and your unique Stenner pump might be a good option for them. Of course it would work for lower runtimes as well...but for calculation purposes it probably would be best if a SET number of hours of pool pump run time (per day) is used throughout the year, and also afairly long pool pump run time” because of the slow injection rate of that particular Stenner pump family.

Nice solution and looks like the wattage is much less than I anticipated as compared to the more standard Stenner pumps like mine. Keep us updated...

@spoonman, I don’t dilute my acid, but I was unaware of the -recommendation- that dilution of acid should be accomplished by adding the acid to water and not vice verse...nice to know. Is that for splashing purposes?

Hi Jonp

Here is some info on not adding water to acid...I won't pretend to be an expert here, but I understand that in the worst case, this can cause an explosion at least when performed with sulfuric acid. I have heard this repeated by others on TFP also.

Here's How To Mix Sulfuric Acid and Water (Safely)
When you mix concentrated sulfuric acid and water, you pour the acid into a larger volume of water. Mixing the chemicals the other way can present a lab safety hazard.

Whether you add acid to the water or water to the acid is one of those things that's important to remember, but you may need to figure out. Sulfuric acid (H2SO4) reacts very vigorously with water in a highly exothermic reaction. If you add water to concentrated sulfuric acid, it can boil and spit and you may get a nasty acid burn. If you're wondering about the temperature change, mixing 100 ml of concentrated sulfuric acid and 100 ml of water initially at 19 degrees C reaches a temperature over 131 degrees C within a minute. The spitting or splashing of acid that results from mixing them in the incorrect order is from the intense heat produced by delayed boiling.

 

[jonpcar]

Hi Jonp

Here is some info on not adding water to acid...I won't pretend to be an expert here, but I understand that in the worst case, this can cause an explosion at least when performed with sulfuric acid. I have heard this repeated by others on TFP also.

Here's How To Mix Sulfuric Acid and Water (Safely)
When you mix concentrated sulfuric acid and water, you pour the acid into a larger volume of water. Mixing the chemicals the other way can present a lab safety hazard.

Whether you add acid to the water or water to the acid is one of those things that's important to remember, but you may need to figure out. Sulfuric acid (H2SO4) reacts very vigorously with water in a highly exothermic reaction. If you add water to concentrated sulfuric acid, it can boil and spit and you may get a nasty acid burn. If you're wondering about the temperature change, mixing 100 ml of concentrated sulfuric acid and 100 ml of water initially at 19 degrees C reaches a temperature over 131 degrees C within a minute. The spitting or splashing of acid that results from mixing them in the incorrect order is from the intense heat produced by delayed boiling.

Spoonman, thanks! I wasn’t aware of how touchy mixing water and acid could be. I am not pre-mixing currently, but good to know if/when I ever change my methodology.