- May 3, 2007
- 18,112
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
I would also keep your testing to the spa since that would reduce the test period and help reduce any algae influence
SWG run time calculations assistance
- Thread starter sbcpool
- Start date
- May 23, 2015
- 25,775
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
If you have any algae in your pool water (mustard or otherwise), it's going to confound the testing and results. I know you think your pool is fine but any kind of active algae growth on the walls would indicate to me that you very likely have planktonic algae in your pool water volume. SWG's are highly sensitive to biological contamination mainly because they produce chlorine at very low rates. Even when algae is in the early planktonic stage (free floating with mostly clear water), it can reproduce fast enough to exhaust the FC supply in the water.
It surprising to me that you can pass OCLT with active mustard algae growth....are you raising your FC to shock levels, turning off all sources of chlorine, measuring at night and then remeasuring in the morning before sun up? Preferably using a deep water sample collected using a pipe, not just a surface sample...
It surprising to me that you can pass OCLT with active mustard algae growth....are you raising your FC to shock levels, turning off all sources of chlorine, measuring at night and then remeasuring in the morning before sun up? Preferably using a deep water sample collected using a pipe, not just a surface sample...
Assuming 24 volts DC and 6 amps, it’s like there are 2 sets of (6) 4volt batteries in series being charged with the sets in parallel. The total amps are 6 amps x 6 cells or 3 amps x 12 cells (36 amps either way).
I just tested all combinations on the cell connector. If you number each connector as shown, the chart below reflects the results:
I'm not raising to shock levels. The last OCLT I ran was starting the evening at 5.6 and 5.4 in the morning if I recall correctly. Otherwise, that's how I'm doing it.
If the standard to test is going to be that the pool can sit below FC 6 with CYA at 50 and not get mustard algae, it's never going to pass in 1,000 years. They will enter the pool and grow at 6 or below with CYA at 50.
Absolutely easier. 3.1 lbs of chlorine per day would raise the spa about 28 per hour, but it's only raising it 8 per hour. There's no way algae is consuming the other 20. At that rate the pool would consume 22 gallons of 12.5% a day.
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I think I have solved the eyeball problem, at least for testing purposes. I got some street elbows and had to grind down the male end a bit to fit the returns, but now the returns are directed down and to the right (if looking into the pool from the edge). The pool's circulation should make a large counterclockwise eddy now. I stuck a 5-foot length of pipe on the last return that had the most bubbles and directed it into the bottom of the deep end at the center of the circulation. Now it is the only return that bubbles at all (and not much), and those bubbles have to rise from 5 feet deep.
I am doing another OCLT tonight. Running the pump now to boost FC and test with new circulation.
Pics or it didn't happen:
I am doing another OCLT tonight. Running the pump now to boost FC and test with new circulation.
Pics or it didn't happen:
- May 3, 2007
- 18,112
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
It's not appreciable different. About 12 lbs.
It was as you suspected: The modifications on the returns made zero difference on FC production. The good thing is that now I can put valves on the returns and regulate the output of the pump.
It was as you suspected: The modifications on the returns made zero difference on FC production. The good thing is that now I can put valves on the returns and regulate the output of the pump.
Forgot to add. OCLT underway. 7.2 FC at 8:00 pm. Double checked at 9:00 pm in case everything wasn't well stirred. Still 7.2. I brushed the sides and bottom to stir anything that might be there up into the water. I'm trying to stack the deck against the OCLT as much as I can. If there's anything "eating" my chlorine I want to make sure and catch it.
I still think your CYA is too low which to me as per TFP isn't recommended. Why wouldn't you bring the CYA upto recommended levels.
- Nov 12, 2017
- 12,682
- Pool Size
- 12300
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Pardon, just doing a drive by. I got dumped somehow into page 4 of your thread and read just a bit there. Quite a story. For what it's worth, and apologies if this was already covered... I had "bare-pipe returns" too. When I replastered the pool they dug them out, cut them back a bit, converted them to 1-1/2" female-thread fittings and then installed eyeballs after the plastering was done. They work great and the circulation improved dramatically. So if you haven't yet solved that part of your issue, you'll be able to...
The main reason is that if the SWG isn't going to produce its advertised output (or even somewhere north of 70% or so), it's not staying in the pool. I am not keen on making my life that much more miserable with liquid chlorine. If I can get it to perform as advertised I will raise CYA. The bag of CYA is sitting in the garage waiting to go. Draining around 50% of my pool would take about two days, too. Something I'm not eager to do.
Question: When the SWG first starts, the instantaneous salt reading will be very high (like over 5,000). As it runs for the next 20 or 30 minutes the instantaneous salt reading slowly falls down to the 3800 ppm range. The average salt displays 3800 as well. Is that 5,000+ at start up each time normal?
I believe so. I have noticed that on my RJ-30+ that the salt reading tends to be high at startup (I don’t think I’ve checked it immediately at startup), but certainly if I check near startup it is reading several hundred ppm higher than where it normally sits.
It calculates the salinity based on the conductivity of the water and that is an estimate at best. It is also highly temperature dependent. It tries to do temperature compensation, but if the water has been sitting in the pipes for a little while then the temperature could be very different than the temp of the water in the pool and it can take a while for everything to settle down and average out. I think that’s why it shows the average salt level, because the instantaneous salt level can be all over the place at times.
Thanks. Makes sense. I forgot about temperature compensation for conductivity.
I'm interested in how they're calculating. My conductivity meter is also temperature compensated and reports 8,280 μS, which means the control unit is using a ratio somewhere around 0.46 ppm salt for every 1 μS conductivity, give or take.
I'm interested in how they're calculating. My conductivity meter is also temperature compensated and reports 8,280 μS, which means the control unit is using a ratio somewhere around 0.46 ppm salt for every 1 μS conductivity, give or take.
http://www.myronl.com/products/solutions.htm
It's important to make sure that the meter is set to salt (NaCl) and not TDS.
The above reference shows the two curves for the conductivity at a specific temperature.
It's important to make sure that the meter is set to salt (NaCl) and not TDS.
The above reference shows the two curves for the conductivity at a specific temperature.
My meter doesn't have TDS. It's just strictly a conductivity meter.
americanmarineusa.com
According to that chart, my salinity is around 4,500. Why would the controller read 15% lower? Perhaps more importantly, if my salinity really was 4500, would that reduce chlorine production by about 70% or would it increase it by having more chloride available to electrolyze?
PINPOINT® Freshwater Hardness Monitor
PINPOINT® Freshwater Hardness Monitor is an instrument for the measurement of hardness in freshwater. The conversions are 33 µS=17.9 ppm=1dH. Good quality reverse osmosis water measures 5–15 µS, while de-ionized water typically measures 0–1 µS. The Freshwater Hardness Monitor is automatically...
americanmarineusa.com
According to that chart, my salinity is around 4,500. Why would the controller read 15% lower? Perhaps more importantly, if my salinity really was 4500, would that reduce chlorine production by about 70% or would it increase it by having more chloride available to electrolyze?
My meter doesn't have TDS. It's just strictly a conductivity meter.
PINPOINT® Freshwater Hardness Monitor
PINPOINT® Freshwater Hardness Monitor is an instrument for the measurement of hardness in freshwater. The conversions are 33 µS=17.9 ppm=1dH. Good quality reverse osmosis water measures 5–15 µS, while de-ionized water typically measures 0–1 µS. The Freshwater Hardness Monitor is automatically...
According to that chart, my salinity is around 4,500. Why would the controller read 15% lower? Perhaps more importantly, if my salinity really was 4500, would that reduce chlorine production by about 70% or would it increase it by having more chloride available to electrolyze?
Because the water hardness meter is reading for TDS, not salinity.
You would need the salinity meter to read for salinity:
American Marine PINPOINT Salinity Monitor + Calibration Fluid Amazon.com : American Marine PINPOINT Salinity Monitor + Calibration Fluid : Aquarium Test Kits : Pet Supplies
Although that one is designed to read sea level salinity levels (on the order of 35,000ppm) so I’m not sure if it would read accurately at the 3500 ppm range that we keep our pools.