NW_Traveler

I've been getting an SNS error on my Balboa spa pack for some time. I usually move the memory jumper from vertical (only one side on) to horizontal and try to clear it, but the SNS error is now coming back more and shutting the tub down. I saw from another thread that replacing the sensors may solve it. Would someone mind explaining which sensors to buy and how to do this? Note for forum moderators: the name Portable Hot Tubs & Spas is really confusing. You should just call it Hot Tub & Spas. Thanks!!

Thanks, Chem Geek! That makes a lot of sense. I'll give that a try.

First, let me thank ChemGeek and Nitro for their system. I've been using it for a few months and the water has been pretty stable. One thing I'm still struggling with is the right amount of cholorine. How many PPM does the average person use per hour? I realize the answer will depend greatly on the person - just looking for the approximate answer. Currently I'm pouring in 5 oz of bleach before we get in. That seems like a lot though. If the hot tub is at 2ppm then 5 oz puts my 355 gallon tub up to 8.8 ppm chlorine which seems like a lot to soak in. I'm putting in 5 oz regardless of if it is one person or two. My wife complains that the tub dries out her skin. Then I usually put in an extra 2 oz after we get out for good measure. I ran a small test last week. Me plus three young kids only took the chlorine from 6ppm to about 3ppm over an hour. I was in the full hour. The kids maybe 30 min. So, seems like 5 oz is a bit much. My other question is on combined chlorine. I'm seeing cc of .4 to .6 pretty much all the time. Is that too much? I super chlorinate / shock to 10ppm once a week and still seeing this level of cc. BTW, my stats if helpful: -355 gallon tub -99 degrees -pH 7.5 -TA 90 -CH 160 -CYA 25 -Borate 50 (gentle spa) Thanks, AC

Part of the confusion might be ounce (weight) vs ounce (volume). I was referring to ounce as volume (i.e. fluid ounce). 1 fluid ounce = 2 tablespoons = 6 teaspoons = ~1.08 ounce (wt) I gave this a try and am still a bit confused. Here's what I did yesterday. I should note that FC was <1 before I started. 1. Added 3.5 tsp of dichlor 2. Soaked for an hour (1 person) 3. Added 2 tbsp (1 oz per above) of dichlor after. Theoretically this should be about right given the rules of thumb, right? 24 hours later I checked the chlorine level and it is 12ppm and CYA is 30ppm. Yikes! This seems really high. I think the goal of the diclor / bleach model is to keep FC low, between 1 - 3ppm, right? Any thoughts? Thanks, AC

The OP stated 1 ounce/day, not 1 tsp/day. 1 ounce is 6 teaspoons, not 2. The rough rule-of-thumb is that it takes 3.5 teaspoons of dichlor, or 5 fluid ounces of 6% bleach, or 7 teaspoons of 43% MPS to oxidize the waste generated by 1 person-hour soak. I have found this to be fairly accurate for me, leaving a residual (~1ppm) free chlorine prior to my next soak. 3.5 teaspoons (.5833 oz) of dichlor will raise FC by 6.8 ppm in your tub. This is what you would need to add after 1 person hour soak. Use the rule-of-thumb and adjust as necessary. After you have added a total of 17 teaspoons dichlor, your CYA will be about 30 ppm and you should then switch to 6% unscented bleach (e.g. Clorox Regular). Thanks, this is making a lot more sense now. I re-weighed, and it turns out my scale is innaccurate at less than 1/2 oz so it was weighing a tsp there. Once I weighed several tsp together it was more accurate. Thanks for clarifying!

I'm a little confused on the dichlor rules of thumb. I saw on one post 3.5 tsp of dichlor per person hour, and here 1 tsp a day. I have a 355 gallong tub, and when I type either of these into the pool calculator I get really high FC levels. For instance, 1 oz of dichlor which is 2 tsp raises FC by 11.7. What am I missing? Thanks, AC