Stenner Install Replacing Jandy SWG

poolneophyte

LifeTime Supporter
Jul 1, 2009
272
Long Island, NY
I've been struggling with a Jandy SWG system for the last nine years. I have replaced several circuit boards, flow sensors and cells during this period. I have found the Jandy SWG system to be unreliable and expensive to fix. To make matters worse, Jandy technical support is unwilling to assist homeowners to diagnose problems and simply tells you to call a pool professional. With each Jandy replacement part that I purchased, I kept getting closer to pulling the trigger on a Stenner pump. This spring, the cell failed again and I decided to scrap the SWG and install a Stenner system.

I decided on a 17GPD @ 100 PSI Stenner model 85MPHP17 mounted on a Stenner 30 gallon gray tank. I priced out the system through Locke Well & Pump ($565.49) and Chem World ($615.59). I then found a sister site to Chemworld called boilerandcoolingwater.com and got the same package for $498.17 including Fedex home delivery. I ordered from them on Memorial Day, the package shipped the following day and arrived on my doorstep the very next day. My advice to anyone pricing out pump is to go to Stenner Build Item Number and then do a Google search using the complete item number.

I installed the system last weekend which involved removing the SWG and doing some piping modifications. The most difficult part was digging a trench for the power conduit between my power center and the Stenner pump location. I have an electrical background so the wiring part was easy. I had a spare 2-pole relay in my Jandy power center which I wired to the load side of the pump relay. This is a safety measure to ensure that the Stenner pump can't run without the filter pump running. After the installation was complete, I dumped 12 gallons of 12.5% shock into the tank and ran a 60 minute test pumping into an empty bleach container. The 17 GPD pump has a +/- 2% accuracy which equates to 88.9-92.5 ounces per hour. My 60 minute test resulted in 106.25 ounces which equates to 17.2% above the rated capacity. I called Stenner technical support and was told that the discrepancy is probably due to the pump tube and that I should replace it with the spare that was provided with the pump. I decided that the flow rate really didn't matter as long as I knew the actual rate.

Now here is the cool part. Last night, I waited until the sun set and ran a FAS-DPD test using the 25mL sample size which uses 0.2 PPM per drop. This test resulted in FC=6.8 and CC=0.2. I then ran the Stenner pump for exactly 1 hour and waited for another 15 minutes for the water to circulate. I used Poolmath to determine that at my tested injection rate of 106.25 ounces per hour it should raise the FC by 5.8 which when added to my tested 6.8 should result in a FC of 12.6. I then ran a second FAS-DPD test using the 25mL sample size and got FC=12.4 and CC=0. I can't believe that the tests show a 0.2 PPM difference between what I calculated versus the actual test!

Thanks to all of the prior Stenner build posts for giving me the knowledge of how to do this. I'd be happy to answer any questions about my build.
 

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jonpcar

Bronze Supporter
Jun 1, 2016
545
Gilbert, AZ
Nice job on the install and good advice on finding a great price on the exact Stenner system you wanted!

I think the preciseness of the calculation between calculated and actual is a somewhat random draw, but is a great story! Haha. I’ve done similar and sometimes it works out and other times I’m like...what the heck? Anyway...congrats!
 

Bama Rambler

Mod Squad
TFP Expert
Bronze Supporter
LifeTime Supporter
Jun 22, 2009
24,129
SouthWest Alabama
Great job. As you noted, the actual output isn't really critical as you'll adjust the runtime of the pump to maintain the FC at your desired level.

I have ours set to run three times a day for 45 minutes each time and rarely do I have to adjust the time.
 

poolneophyte

LifeTime Supporter
Jul 1, 2009
272
Long Island, NY
I have ours set to run three times a day for 45 minutes each time and rarely do I have to adjust the time.
Bama,

Thanks. Since I ran my 60 minutes test 2 nights ago, I haven't had to add chlorine. Tonight will be the first time I have to run the Stenner. I plan on injecting the chlorine while its dark for maximum contact time. It's going to be a learning process but I think I'm going to like the Stenner over the Jandy SWG.
 

poolneophyte

LifeTime Supporter
Jul 1, 2009
272
Long Island, NY
Stenner Tech Support,

I didn't know that you had a presence on TFP. So far I'm impressed with your product and support. I may reach out for a replacement of the tube which was so far out of tolerance but maybe it really doesn't matter. It's nice to know that you are here if any TFP members need help.
 

DanF

Silver Supporter
Mar 17, 2019
269
Chandler, AZ
Thanks for sharing your install, @poolneophyte. I'm looking for a way to automate adding chlorine to our pool. I like the way your pump attaches to the tank. Did you consider housing the pump in a weather-proof enclosure? Not sure how that would work with your tank.
 

Skurzban

Member
Jul 3, 2020
14
West Hills, CA
Hi. I am pretty handy and the Stenner pump and 15 gallon tank look like the solution I have been wanting for years to keep my pool chlorinated AND alleviate the need for me to manually add chlorine daily during the summer. That being said - everything looks pretty straightforward except how I attach the outflow from the pump to my system. Will I need to cut out a section of pipe? Is there an easy way to install the tube into the existing PVC pipe? I assume it is placed in the pipe that exits the heater and returns to the pool?
 

Bama Rambler

Mod Squad
TFP Expert
Bronze Supporter
LifeTime Supporter
Jun 22, 2009
24,129
SouthWest Alabama
The easiest thing to do is just drill and tap the return piping for 1/4" NPT and thread the injection fitting into it.
You can also cut out a piece of pipe and install a reducing tee with a 1/2" threaded branch, then reduce down to a 1/4" npt.
 
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gary300

LifeTime Supporter
Dec 15, 2014
568
Riverside California
I went from using Tabs (my bad, hadn't run across TFP yet) to manual;y dosingl liquid Chlorine every day. Being that I did not have anyone who could watch my pool and add Chlorine for me every day while I went on a 1 or 2 week vacation most Summers, I installed a Stenner pump (45 MPH10 fixed rate mounted to a Stenner 15 Gallon grey tank). This worked fine for a couple of years, but increasingly I started to have reliability problems with the Stenner setup. I know that I had to replace the Pump Tube each year, and all of the tubing, injector and duckbill when I could see any of that plugged up with salt residue. All of that I could handle, but I still had to go to the store and cart home 10-20 Gallons of bleach in the Summer months. I could not keep my 15 Gallon Stenner tank full, because in the Summer our temperatures here are close to 100 degress each day. No room to bury a tank, so the bleach got degraded every day. I used to have to add 1/2 Gallon of 10% bleach a day during the Summer when using manual chlorination, but with the degradation it started running around 1 Gallon a day from the Stenner to keep my FC happy (5 PPM).

Got fed up with all that, so last year around May, I installed a Pentair IC60 SWG (Pentair because I have Pentair Easytouch automation). Before I installed the SWG I tested my salt content (thanks Jim for saving my behind) and it was already at 3200 PPM due to using liquid Chlorine for years.

There are no words to express how happy I am with the SWG addition to my pool. I was an idiot not to go to SWG years ago. No more hauling and storing Bleach, which was a giant PITA (I am not a young man). My SWG so far has been super reliable, and only requires a Salt percentage change from time to time.

I am not trying to berate your excellent job of installing your Stenner pump. I am sure, as I was that you will be very happy not to pour Bleach into your pool each day. My Stenner did save me from have to manually dose each day and to have a means to add Bleach when I was not home which was a great help. All I want to convey is that after the Stenner, it might be that SWG could be the next (and hopefully last) step.

Gary
 
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