Acid Injection - Proposed Set Up - Questions & Comments

Jaimslaw

LifeTime Supporter
Jun 5, 2015
321
San Diego, CA
My 45mp2 is on its way (10 gpd/25psi), along with Stenner's 15 gal. tank. Will time it separately from the pool pump with Woods 50015 Outdoor timer. Set up is to address PH creep from a SWG pool as dual spill over spa creates a lot of aeration andabove average acid demand (notwithstanding having made a career out of TA adjustments). I am going with a fixed rate pump vs variable to cut down on part maintenance and possibly avoid sound issues (clicking as some have reported).

As most threads relate to injection of Chlorination, I am hoping to improve safety margins if possible to minimize risks attendant with leaks caused by an issue with one or more of the components of the system. So here is what I'm thinking. Feel free to weigh in if you have any other suggestions or to point out flaws.

1. Line leaks: I am going with the 1/4" UV tubing, and assume this will be appropriate for MA. (BTW, anyone know if MA causes greater tube breakdown than Chlorrine?). Since annual tube replacement appears to indicate this as a primary breakdown point (potentially), annual replacement of the tubing sounds like a must, to be sure. But I'm thinking of also running the 1/4 UV tubing through, say, a 1" clear tubing. I'd use a little silicon adhesive at the hook up ends or even fashion a simple rubber collar. Then I’d insert a T in that clear line, attach a line to it and run a drain line back to the tank to carry any tube leakage. My house backs up to a canyon so I am concerned about rats chewing through my 1/4 line. Again, I would be less concerned if the line were only to leak chlorine.

2. Insertion Point: I will not be syncing the Stenner pump to my pool pump. With risk that an out of sync system will have acid being pumped into 2" pool lines that are not moving any water, I plan to place the insertion point as far downstream as possible - perhaps just before the return line heads into the ground. My thinking there is that this location means there will be a considerable amount of PVC pipe between that insertion point and my heater (with my SWG configuration thankfully adding to the overall length of PVC pipe from insertion point to the point the pipe enters the heater). Normally, I would prefer to have he insertion just before the SWG so as to let the normal acid injection help clean my SWG cell; but should there be build up of acid from an out of sync running of my Stenner Pumo, my heater is just too close to the SWG - I'd hate to have acid concentrated water backing into my heater in that event.

3. Check Valve: The 45MP2 does not have the built in check valve but I guess that’s why Stenner sells an inline check valve. Still am unclear if check valves are a weak link (blockage) and not sure about that potential). Anyways, my understanding is that if there should be any Stenner pump tube leaks, water won’t pump it out of that tube leak opening under the force of the running pump. I understand this is the reason for a check valve. But given my set up (See #1 above), I’ll need a check valve so that a tube leak doesn’t end up pumping water into my proposed second outer “backup safety tube and then into my acid storage tank via the overflow line set up referred to in the #1 configuration above).

4. Safeguard Against Out of Sync Timer: I have a Aqua Logic AQL - PS4 automation with an empty AUX 1 relay. Not sure, but I don’t see why I can’t have my Stenner Pump Timer (Woods 50015 Outdoor timer) powered from this relay, which of course will pass power to run the Stenner pump per what I program it to run. I believe the AUX 1 relay has a timeclock capability, which I would then set to coincide with the timing of my pool pump. If the timer should screw up and want to run the Stenner Pump at midnight, for example, there would be no power to do so, since the AUX 1 relay would be timed to be off when the pool pump is not running. The only weak link might be that the Woods Timer, when not constantly fed with power - as will be the case for about 18 hours - will not hold its settings. If that is the case, I guess I would have to find a better battery back up timer that would hold the settings for a longer period (ie the 18 hour the timer does not have juice to it). I guess I could just hook up the Woods timer to my pool pump relay instead to feed it power whenever the pool pump is on; but I have some concerns that I could exceed the draw rating of that pool pump relay and possibly burn it out if I am pulling power both for the pool pump and the Stenner Pump. The foregoing reflects my lack of sophistication in matters pertaining to relays and their draw capacities, among other of my knowledge shortcomings.

No doubt, some of this might be considered overkill. And I’m sure plenty of you have run your acid injection system without issues or thinking any of this is even necessary. That’s understandable and reasonable. But I hope to hear from those of you who can help me with flaws vs. being overly cautious (the latter being an element of my nature).

Cheers.
 
I would wire the Stenner to the Aux 7 ( either directly or through a wired plug ). That way you have complete control and can be assured the Stenner is on only when the pool pump is on. You can also put the injection point just before SWG and not have any worries of acid backing into your hetaer, since the Stenner will only come on when pool pump is on. Rat's , one taste of acid should break them of chewing on your lines. LOL I like your idea in #1
 
I would wire the Stenner to the Aux 7 ( either directly or through a wired plug ). That way you have complete control and can be assured the Stenner is on only when the pool pump is on. You can also put the injection point just before SWG and not have any worries of acid backing into your hetaer, since the Stenner will only come on when pool pump is on. Rat's , one taste of acid should break them of chewing on your lines. LOL I like your idea in #1

I don't think I have an Aux 7 - just the Aux 1 and 2, which will carry the line voltage to the timer and via the timer to the Stenner Pump. Here is my Aqua Logic PS 4 Panel - the far right relay is now used for a equipment light I never use so would use that relay:

IMG_20151004_132942_342_zps3xgh0tfg.jpg


As far as those rats, I think they would just use any acid lingering in the line when not running as mouthwash. I have to keep my 1/4" drip irrigation lines buried from these critters so anticipate some risk of one taking a bite and cause of leak to develop. Would make my day to see a dead rat reduced to an acid rubble via biting into it under full pressure.

Might just move that insertion point if I allay all fears of an out of sync building up acid and wreaking havoc to a $3900 heater. Plus I've definetely warmed up to the suggestion of a another TFP poster who recommended it be placed near the SWG to add some extra cleaning of the SWG. But then I might get real lazy and just thread it into my long abandoned Rainbow 320 Chlorinator's extra port. The only issue there is that an automated valve housing sits close to the port of the puck chlorinator such that there may not be enough room for insertion at the port of the longer Stenner check valve insertion assembly. That thing looks like its about 4 or so inches long and I only have about a 2-3" space between the Rainbow lower Chlorinator port and the adjacent automated jandy valve housing.
 
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couple points. We are building as I type and pumps are in the mail I ordered a 3GPD for acid and 10GPD for Chlorination. 3GPD is 8 oz an hour vs 27 oz an hour for a 10GPD do you need that large of volume per hour each day? Most people add acid couple times a week and still manage to stay in the window. 10GPD will no doubt work jut in very short intervals unless your demand is exceptionally high.

A tube in a tube will work but may be over kill. If you want to do it what I would do is on the acid tank suction side run the secondary tube down into the same opening as the 1/4 comes out of just get a larger grommet and insert it in only an inch or two into the tank well above the acid level no T needed on that side. If you get a break on the suction side you are only going to leak what is in the line between the tank and the pump assuming the line does not dip below the liquid level before going up to the pump creating a siphon. we are talking a few ml not several zo or gallons. On the output side you can do a second tube to protect from rats or whatever but that on I would just run as near to the injection point as possible and leave it open to the gorund. If you get a break on that side it will get flushed with pool water when the pump runs and be fairly safe if a bit messy. Stenners use 3 rollers and 2 are always in contact with the tube so I can't imagine a scenario where the pressure side makes it into the tank even with out a check valve. The only weak point I can think of is the roller tube and if you replace it every year I think you will be fine. as for the 1/4 tube Santoprene has good acid resistance but again you can't go wrong with yearly replacement.

On to the relay idea, pump amp draw is low around 1.7amp at 120V, I looked up you panel and it says aux1 is a high voltage relay no amp value but I can't imagine it not handling the pump, call the vendor if you want to be sure. So what I would do is power the timer with an always on outlet plug a short 3 prong extension cord into the output of the timer. In the middle of the extension cord carefully cut away the sheath and expose the wires leave the white and green intact and cut the black and run each end into the relay, plug the pump into the other end of the cord. the timer will keep it's schedule and pass power to the input side of the relay but the Stenner will not be able to turn on unless panel is running the pump and the relay is energized. You could do the same by cutting into the Stenner cord but that would void the warranty better to sacrifice a $9 extension cord.
 
Good comments.

I bought the higher 10gpd model not really knowing much about the different rates and what my demands would be, and I don't think there was a price difference between the 10pdg and your 3gpd, so yes, in hindsight, I would have chosen the one you bought. But as you said, it will not really be a factor in terms of the fine tuning process of getting the PH levels to stabilize.

I like the splicing idea as it does serve to keep the timer powered up all the time. But if my timer retains its settings during the 18 hour shutdown, I think my configuration will be cleaner...i.e. not needing a junction box to be code compliant when dealing with the splice method. My power cord for the timer that is hooked to the PS-4 Aux relay will have a clean exit out of the panel with a wire collar, which cord will hook into the timer. But alas, I plan to void the warranty of the Stenner as I need to replace the short 6ft pwr cord with a 12 footer... my power source referred to above is that far from where my tank/pump setup will be. Using an extension code won't do to extend that 6 ft power cord as that too is not code compliant...extension cords cannot be used as permanent wiring per the IRC and UEC. I can live with the void warranty as Stenner has an absolute great reliability rating of their products...tops in the industry.

Your comments about the tube configuration has given me pause to think about altering my set up, though I still plan to have the outer clear tube as I got about 9 feet of it still sitting in my garage attic. Might as well put it to use. Besides, it's war against the Norway rights in my canyon (huge). They just don't nibble at those lines...they bite them in half. Probably thinking that tube will have water like my black drip line tubes they are always after. Drought conditions here in So Cal has really had them doing overtime trying to get water. My pool pad is right up against the canyon.

Maybe you can post pics of your set up...I'll do the same. Still a little curious about how to approach the fine tuning process of timing the acid injection. Might just start off running water and having a 1/4" tube spigot to measure quantity into a container before loading up the tank with the real stuff.

Thanks again for your insight.

Cheers.
 
On to the relay idea, pump amp draw is low around 1.7amp at 120V, I looked up you panel and it says aux1 is a high voltage relay no amp value but I can't imagine it not handling the pump, call the vendor if you want to be sure. So what I would do is power the timer with an always on outlet plug a short 3 prong extension cord into the output of the timer. In the middle of the extension cord carefully cut away the sheath and expose the wires leave the white and green intact and cut the black and run each end into the relay, plug the pump into the other end of the cord. the timer will keep it's schedule and pass power to the input side of the relay but the Stenner will not be able to turn on unless panel is running the pump and the relay is energized. You could do the same by cutting into the Stenner cord but that would void the warranty better to sacrifice a $9 extension cord.[/COLOR]

aux one will run the stenner I have a 8 relay version and use one of the aux ports for my stenner pump. That said I don't see the point in using an external timer if your aux 1 is available. I have mine setup with the stenner wired directly to the aux relay and i can fully control and schedule the stenner from my pool timer and not need an additional timer.
 
aux one will run the stenner I have a 8 relay version and use one of the aux ports for my stenner pump. That said I don't see the point in using an external timer if your aux 1 is available. I have mine setup with the stenner wired directly to the aux relay and i can fully control and schedule the stenner from my pool timer and not need an additional timer.

True, but I wanted to be able to inject the acid in several daily doses with intervals bewteen the dosing - the timerclock for the PS-4 Aux relay will just allow a one time frame dosing on/off interval. But hey, I'm still on the learning curve when it comes to dosing. It seems like everyone is injecting in multiple dosing intervals. Is that due to wanting a more even introduction of the acid or chlorine vs. an all at once dosing time frame? Always wondered about that.





Maybe I will cut out that $16 timer and do as you suggest, unless there is some reason or advantage for injecting my acid in spaced intervals during the pump cycle. But will be bummed if your suggestion means this entire set up of my systyem will be over in a short time - that's no fun....I'll be left with too much extra time on my hands and no other projects to keep myself occupied.:cool:
 
I don't think it matters if its one dose vs several small ones.

I'm moving in the single dose direction; remain curious and befuddled by so many who are doing their chemical injection in several timed intervals. I would think getting one dose injected early in the pool pump cycle would give more time for distribution or assimilation of the acid or chlorine.
 

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If you do find that the 10GPD makes it hard to fine tune you can convert your pump to a 3GPD by changing the pump tube to a #1

That's great to know. Since I haven't yet received my pump to go over its configuration, what exactly is involved in changing the pump tube to a #1? Do I order a #1 tube from Stenner?

I may need to do just that. My pool panel relay timerclock can be set only in 15 minute increments. That means little, if any, fine tuning. But maybe your suggestion will give me a shot at getting the right amount injected.

I will be looking over other posts that had info about the amount of output of the various Stenner models and see if I can determine whether the 10GPD will be too much to be able to work with the 15 minute intervals that I am limited to on the timerclock of my PS-4 Aux 1 relay (to which I was thinking of hooking up to the Stenner).
 
Looking at the Stenner Pump specs for the 45 Fixed Rate series, the 3 GPD pump will output .27 of an ounce per minute, and the 10GPD pump (mine) will output .89 ounces per minutes. Since my timerclock on the PS-4 relay allows only 15 min intervals, that leaves me with an output of either 4.05 oz (ie per 15 min interval) if I reduce my 10 GPD pump to a 3GPD via changing the Stenner tube OR, I will have an output of 13.35 ounces per 15 min interval with the 10GPD pump.

This does not leave a whole lot of adjustment capability, as my injection quantities would look something like this:

10GPD Pump
= 13.35 oz if I set it for one min 15 min interval (ie, amt of acid added daily)
= 26.70 oz if I set it for two 15 min intervals (ie, amt of acid added daily).

If I convert my 45MP2 to a 3GPD pump, acid injection amount options would be:

3GPD Pump
= 4.05 oz for one 15 min interval
= 8.10 oz for two 15 min intervals.

With so little flexibility here, looks like I'm back to incorporating a separate timer for the Stenner output and doing one of the two wiring configurations referred to in this thread to ensure the Stenner pump runs only when the pool pump is running.
 
the 15 minute timer interval is the main reason I chose the 3 GPD pump (also i'm using mine for chlorine which is higher dosage than acid anyway). Changing the tube is very easy requires no tools and takes about 1 minute. The tube typically needs to be replaced ever year anyway.

I would try to avoid the external timer at first and see how it works. You can always add it later.
 
the 15 minute timer interval is the main reason I chose the 3 GPD pump (also i'm using mine for chlorine which is higher dosage than acid anyway). Changing the tube is very easy requires no tools and takes about 1 minute. The tube typically needs to be replaced ever year anyway.

I would try to avoid the external timer at first and see how it works. You can always add it later.

Agreed, but do I need to order that #1 tube from Stenner? That is, is it a maintenance replacement part for the 3GPD pumps? Today I will look at the scematic online and try to find out where that tube is located, and the step to take to replace it.

Still have some hesitation about a very limited number of dosage options though. It would almost be a lucky shot in the dark if one of those 2 3GPD dosing options would work (one being via the 15 min dosing interval and the other being a 30 min dosing interval - don't see going beyond 30 minutes).

Thanks again.
 
I will definitely post Picts of my setup when done but it is going to be a few weeks at least lots going on and the yard looks like a bomb when off. My original plan was to use septate timers and get them to power the dosing pumps at the same time as the pool pump via high voltage relays but I just found out that PB is installing a Zodiac Z4 panel nice surprise since all the other builders were just direct powering the pump and using the onboard controls. Thus far this builder has gone so far above and beyond the other quotes he is either losing money or the others were trying to rip us off, but I digress. It sounds like the Z4 is similar to what you have just Jandys version of it so we may end up with a similar build.
You may be able to get the 15 min interval to work if you are willing to dilute 2 to 1 or even 3 to 1 means you will have to refill a bit more frequently but if you have a 15gal tank I think you will still get weeks at a time out of it. From what I have read diluting acid is not a problem but diluting chlorine can be problematic not sure what the difference my guess would be something about the chlorine oxidizing the stuff in the tap water used to dilute.
Not to complicate your build any more but I am a bit of a gadget geek so part two of my build will be to automate the dosing even more by adding a PH sensor / controller they can be found for $80 to $100 on eBay. I want to wait because from what I have read acid demand can be fairly consistent so the sensor may not be needed. I do know the sensors need to be replaced about once a year at a cost of around $20 and have to be calibrated once a month on average.
 
Re: Acid Injection - Proposed Set Up - Questions & Comments

here is a 2 pack of tubes to make yours a 3GPD unit.

Stenner #1 Pump Tube PK2 UCCP201 | Zoro.com

Thanks for that info. I guess its decision time: go with a separate timer or convert my 10GPD Stenner pump to a 3GPD output using that tube kit and taking a shot at getting good PH levels using the two dosing schedule options (Ie a 15 minute run that injects 4.05 oz or bumping it up to a 30 minute run that will inject 8.10 oz of acid. Me thinks it could be a long shot that one of these two dosing intervals will work. My guess is that with fluctuating TA levels and what not, it might be quite a long shot to obtain optimal PH levels with just these to dosing options.

Still glad though that I chose a fixed rate and not a variable rate Stenner pump.

- - - Updated - - -

I will definitely post Picts of my setup when done but it is going to be a few weeks at least lots going on and the yard looks like a bomb when off. My original plan was to use septate timers and get them to power the dosing pumps at the same time as the pool pump via high voltage relays but I just found out that PB is installing a Zodiac Z4 panel nice surprise since all the other builders were just direct powering the pump and using the onboard controls. Thus far this builder has gone so far above and beyond the other quotes he is either losing money or the others were trying to rip us off, but I digress. It sounds like the Z4 is similar to what you have just Jandys version of it so we may end up with a similar build.
You may be able to get the 15 min interval to work if you are willing to dilute 2 to 1 or even 3 to 1 means you will have to refill a bit more frequently but if you have a 15gal tank I think you will still get weeks at a time out of it. From what I have read diluting acid is not a problem but diluting chlorine can be problematic not sure what the difference my guess would be something about the chlorine oxidizing the stuff in the tap water used to dilute.
Not to complicate your build any more but I am a bit of a gadget geek so part two of my build will be to automate the dosing even more by adding a PH sensor / controller they can be found for $80 to $100 on eBay. I want to wait because from what I have read acid demand can be fairly consistent so the sensor may not be needed. I do know the sensors need to be replaced about once a year at a cost of around $20 and have to be calibrated once a month on average.


- - - Updated - - -

I think I recall some negative comments about the sensor/controller for injection systems. But hey, I'm with you on the gadget geek profile. I say go for it and whatever your experience is, post it and we all will benefit from your feedback, good or bad.
 
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