Stenner Pump System for stand alone Hot Tub?

[mastac741]

Hi --

I recently purchased a Stenner Pump for my pool. It's almost ready to go, just waiting for an electrician to hook it up. I'm thinking of buying a stand alone hot tub (unfortunately my pool did not come with a spa). I've been reading the forums about choline vs bromine for hot tubs. Still seems like you're adding chlorine a lot manually. Looking for a more maintenance friendly solution.

Anyone hook up a Stenner pump to a hot tub?

 

[Bama Rambler]

I don't remember reading about anyone using an injection pump for a standalone spa, but it's certainly doable. Do you know the approximate size of the spa you want?

The only caveat of trying to use an injection pump for a hot tub is the variability of the FC required because of varying loads (people) in the tub. Also, manually adding bleach to a hot tub is a pretty minor task.

You'll need the smallest pump they make and a timer capable of minute or parts of a minute adjustments. You may even need an adjustable model pump so you can adjust it down enough so as not to over chlorinate the tub.

Having said all that, I'd recommend manually chlorinating the spa until you get a feel for how much bleach you need, and how much work it really is.

 

[mastac741]

I'm thinking of getting a 8-person hot tub. I worry that all the piping is the flexible PVC piping and if that would cause issues because the fitting the allow the stenner injection site is not flexible.

 

[waterl0gged]

Been using a similar (but much cheaper) DIY system in our 400G hot tub for some years now .
I just use a small peristaltic pump system hooked up to a timer . Its a very small peristaltic pump (designed for saltwater/reef fish tanks) and dispenses 1.1 ML per MINUTE .
I have it hooked up to dispense 8.25% bleach for approx 15-20 minutes twice a day (for our hot tub normal usage) . The small pump we use dispenses VERY small amounts VERY slowly, so the amount just gets controlled by a timer. Literally, it is just a drop of bleach , maybe every 2-3 seconds ! The peristaltic pump is perfectly timed to kick-on when the filter cycle is in operation , twice a day .
I have hooked it up to various parts in the hot tub plumbing over the years , but the bleach is too caustic, and can cause damage . I finally drilled a small 1/4" hole at the top of the filter "scoop" area , but under the lid(so it cant be seen) . I protrude the small 1/4" feed line though the hole (fits snug) and it slowly drips bleach directly into the turbulent filter box water as the pumps run in filter mode .
I just use bleach bottles direct . 1/4" tubing sticks into the bleach bottle, up to the small peristaltic pump , then out to the hot tub .
This is the pump I use .............
http://www.bulkreefsupply.com/brs-2-part-doser-1-1-ml-per-minute.html


I have two of these pumps, so I have a spare back-up in case one fails , but I haven't had to use it . Been running the hot tub for a few years now like this, and it works perfect ! These little pumps, with the Santoprene tubing can handle the bleach just fine.
I go through approx 1 gallon bottle of bleach every other month .......usually slightly longer . Great when we go away for vacation , and daily use . I don't have to do much for maintenance besides test water parameters once in a while. , to see if the pump timer needs to be changed a little once in a while, but its rare. Once its all set-up , it works pretty well .
I have had the pump hoses go bad occasionally , but they are cheaply replaceable ($12.99 each) as well (They kind of get "sticky" and soft after about a years use). Once every few months I do clean out the 1/4" lines as they can clog with bleach residue . PH does seem to climb slowly , so either I drain and refill every few months , or just add some muriatic acid in SMALL amounts to bring it down once in a while.

Been working great for some years now ........... Love that I dont need to add clorine/bleach on a daily basis. Our hot tub is crystal clear ALL the time !

Can take some pics of my set-up sometime if you are interested . (Whole system is enclosed in the hot tub shell, so may be a few days before I get time to access it again) .

 

[mastac741]

Wow, that sounds like a sweet setup. I'd appreciate any pictures of your setup. I'm already sold, so I'll try to copy what you've done. What kind of tubing do you use? (Just get it at Home Depot)?

 

[waterl0gged]

O.K. , had to check the bleach bottle to make sure I wasn't running empty , so I got some pictures for you .

Whole system is self contained within the shell of the hot tub . It is not outdoors, but in our unheated garage . Wanted to make sure bleach bottle wouldnt freeze , so I made sure it had some warmth within the shell of the tub .

Basically , a 120v wire with an inline GFCI breaker feeds the 120V outlet under the tub (outlet is also GFCI). Then the digital timer is plugged in the outlet to control the peristaltic pump . The pump pulls from the bleach bottle directly under it which sits nicely in the corner of the hot tub shell . The output of the pump goes through a very snug fitting hole at the very top of the hot tub filter box . The peristaltic pump timer is timed to only turn on during the times that the hot tub filter cycles are running (twice a day) . I dispense approx 20 minutes of bleach for each cycle , twice a day . That spreads out the chlorination process a little bit . So, 40 minutes of pump run time at 1.1 ML per minute of bleach goes into the hot tub daily . About 1.5 oz . That is about perfect for our hot tub usage (yours may vary) .
As you can see , in the last picture , our hot tub is crystal clear . I have NOT added anything manually to the tub in months ! Proof is in the pudding , as they say .
I even added one pic of the pump in action "dripping" , so you can see it does work .
Oh, the tubing I use is just simple soft and pliable tubing I got from Lowes . I had my doubts it would hold up to the bleach, but it has been perfect . I will see if I can dig up the exact line I used for you .
Tubing inside the peristaltic pump , comes with the pump and is a Santoprene tubing. Easily replaceable and cheap ($12.99). I usually replace it once a year .
Also, these little pumps will NOT back siphon , so as soon as the timer kicks the pump on, it will start dripping instantly . No priming needed .
If you have any questions , just ask ! Hope this helped .......

 

[mastac741]

Thanks for the info! You're the man! This is going to save me from having to go out in the cold night to put in chlorine in my hot tub!

 

[waterl0gged]

Thanks for the info! You're the man! This is going to save me from having to go out in the cold night to put in chlorine in my hot tub!

No problem , good luck with the new tub , and DIY automated bleach project .

Also, forgot to add ...........you can NOT just start off from square one adding bleach. You will need to get you CYA up a bit with some hot tub Dichlor first . Usually takes us a week or two , then bleach after that . You should aim for a target of about 30ppm CYA level .
BTW, in hot tub speak , its called the Dichlor / Bleach method .
Here is a good read on that ........... Its under the "Sanitation" header .

http://www.troublefreepool.com/threads/9670-How-do-I-use-Chlorine-in-my-Spa-(or-pool)

 

[mastac741]

Thanks again!

 

[mastac741]

I finally got my hot tub ordered and installed. I ended up buying a Marquis Vector 21 V94B 400 gallon 8 person hot-tub. I like the tub, but after spending $12k, I'm hesitant to drill into the tub. What are your thoughts for inserting the chlorine tube into the plumbing? I know you said that you feel the chlorine can damage the equipment.

I tried the bromine/bromide 3 step-combo everyone uses on TFP, but I don't like the smell of bromine. At least in my pool using just chlorine, I don't smell anything. I really would like to go back to chlorine only and use the peristaltic pump. I'm worried about the pump breaking in the Colorado winters and the bleech freezing. Any thoughts?

 

[waterl0gged]

Sorry, haven't checked in lately .......
The only problems I have ever had with the peristaltic pump system I use , is when it was plumbed inline with the hot tub plumbing. It was just a matter of time before the plumbing, tubing, or connections broke down from the 100% 8.25% bleach and started leaking. EVERY TIME ! I went through about 6 different plumbing entry points, and none of them worked for the long haul. Eventually I would get a leak . I even tried using my hot tub ozone port that wasnt hooked up, and that eventually broke down and leaked too .
The ONLY way I have had this to be truly leak proof and dependable, was when I drilled the shell of the hot tub , so the output of the 1/4" bleach line was independent from the hot tub plumbing, and ABOVE the static hot tub water line. So .......... NO leaks ! The 1/4" line may clogg, break down, ect, but will never let the hot tub water leak out now.
I cant even remember how long this has been trouble free and rock solid dependable for me now. Other than cleaning out the tubing once in a while , replacing the tubing maybe once a year ...........going on two with mine now , and replacing the dosing pump tube set , maybe once a year ...........again going on two with mine now.
Oh yea .............have to remember to change out the bleach gallon jug maybe every month to month and a half . I am down to about 30 minutes of run time @ 1.1ml per min .

Our hot tub is in our garage, so I havent had to worry about freezing temps much ..........but I did have this system outdoors for a while . It worked well when it was fully self contained within the hot tub shell (thats why I originally installed it that way) . The pump, tubing, and bottle of bleach is all within the hot tub shell , and I never had a problem with freezing in sub zero temps. . Within the hot tub shell , is PLENTY of heat to keep that stuff from freezing as long as the hot tub is running and up to temp . My pictures dont show it, but there is a panel and insulation that covers everything (its not just open like the pics show).

Thats it ............if you need any more help , let me know.

Congrats on the new tub ! Thats a nice one. Ours is also a 400g , and I couldn't imaging going any smaller !

.............just drill the hole ! Once and your done. Beats opening up the hot tub shell all the time looking for leaks the bleach has caused (been there , done that !) . Your hot tub will never leak drilling above the waterline .

 

[YippeeSkippy]

Just hooked up our new Saltron Mini salt water chlorine generator for hot tubs/spas and LOVE IT!! Worth checking out, around $170.

Maddie

 

[Bama Rambler]

... I'm hesitant to drill into the tub. What are your thoughts for inserting the chlorine tube into the plumbing? I know you said that you feel the chlorine can damage the equipment.

If you use the injection fitting that comes with the Stenner pump or use 100% PVC fittings you should be fine. Tons of people use the tubing and fittings that come with the Stenner pump to pump 12% bleach and don't have a problem.

As for damaging the equipment, given the very small amount of bleach you'll be injecting and the immediate dilution of it, you won't have an issue with damaging any equipment. Again, a lot of people inject 12% bleach directly into the suction of their pumps. I did it for several years until I got the Stenner pump, and never saw any ill effects of it.

 

[mastac741]

If you use the injection fitting that comes with the Stenner pump or use 100% PVC fittings you should be fine. Tons of people use the tubing and fittings that come with the Stenner pump to pump 12% bleach and don't have a problem.

As for damaging the equipment, given the very small amount of bleach you'll be injecting and the immediate dilution of it, you won't have an issue with damaging any equipment. Again, a lot of people inject 12% bleach directly into the suction of their pumps. I did it for several years until I got the Stenner pump, and never saw any ill effects of it.

Thanks. That's reassuring. I bought another Stenner pump (I have one for my pool which works great). I just bought the PVC fitting with the 1/2" tee to screw the Stenner injection fitting. I'm new to flex PVC piping - I'm used to the hard stuff that I use with my pool. I'm assuming I do everything exactly the same with the primer and glue.

- - - Updated - - -

Sorry, haven't checked in lately .......
The only problems I have ever had with the peristaltic pump system I use , is when it was plumbed inline with the hot tub plumbing. It was just a matter of time before the plumbing, tubing, or connections broke down from the 100% 8.25% bleach and started leaking. EVERY TIME ! I went through about 6 different plumbing entry points, and none of them worked for the long haul. Eventually I would get a leak . I even tried using my hot tub ozone port that wasnt hooked up, and that eventually broke down and leaked too .
The ONLY way I have had this to be truly leak proof and dependable, was when I drilled the shell of the hot tub , so the output of the 1/4" bleach line was independent from the hot tub plumbing, and ABOVE the static hot tub water line. So .......... NO leaks ! The 1/4" line may clogg, break down, ect, but will never let the hot tub water leak out now.
I cant even remember how long this has been trouble free and rock solid dependable for me now. Other than cleaning out the tubing once in a while , replacing the tubing maybe once a year ...........going on two with mine now , and replacing the dosing pump tube set , maybe once a year ...........again going on two with mine now.
Oh yea .............have to remember to change out the bleach gallon jug maybe every month to month and a half . I am down to about 30 minutes of run time @ 1.1ml per min .

Our hot tub is in our garage, so I havent had to worry about freezing temps much ..........but I did have this system outdoors for a while . It worked well when it was fully self contained within the hot tub shell (thats why I originally installed it that way) . The pump, tubing, and bottle of bleach is all within the hot tub shell , and I never had a problem with freezing in sub zero temps. . Within the hot tub shell , is PLENTY of heat to keep that stuff from freezing as long as the hot tub is running and up to temp . My pictures dont show it, but there is a panel and insulation that covers everything (its not just open like the pics show).

Thats it ............if you need any more help , let me know.

Congrats on the new tub ! Thats a nice one. Ours is also a 400g , and I couldn't imaging going any smaller !

.............just drill the hole ! Once and your done. Beats opening up the hot tub shell all the time looking for leaks the bleach has caused (been there , done that !) . Your hot tub will never leak drilling above the waterline .

Thanks for the info. I'm having serious drill anxiety after spending $12k on this sucker. I think I'll try to inject into the piping first. Piping is always easy to replace.

 

[palatiger]

Thanks. That's reassuring. I bought another Stenner pump (I have one for my pool which works great). I just bought the PVC fitting with the 1/2" tee to screw the Stenner injection fitting. I'm new to flex PVC piping - I'm used to the hard stuff that I use with my pool. I'm assuming I do everything exactly the same with the primer and glue.

- - - Updated - - -



Thanks for the info. I'm having serious drill anxiety after spending $12k on this sucker. I think I'll try to inject into the piping first. Piping is always easy to replace.

mastac741 did you install this bleach pump set-up? I searched the internet for bleach pump spa and came across this thread. I have a tub in a location that I only visit once a week normally... keeping FC level up is impossible and I do not like the smell of bromine. Thanks for any insight!