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View Full Version : Can you get that 'chlorine/chloramine' smell from an SWG??



human
09-21-2006, 08:08 PM
This question has probably been asked, but in the research I've done on this site, I could not come up with anything.

We had our pool replastered recently, and I used the BBB method (thanks to this board) for the first two months to make sure everything had cured properly before pouring in my salt and activating my SWG.

Everything is finally in check, I've got my SWG set at 3200 PPM's and my chlorine level at appx 3ppm and all my other levels are pretty much in check-I've just got to watch the PH level pretty closely. I'm handling all my pool maintenance, and my pool looks 100% better now than it ever did with a pool service-thanks to all the tips and advice I've found here.

My question is, does the chlorine generated by the SWG cause any chloramines to occur in the pool?? (I'm no pool expert, but I've learned through this site that the strong pool odor is chloramines, not the actual chlorine itself)

My wife seems to think she still smells that chlorine (chloramine) odor, even though we've had the salt in the pool and I have stopped adding bleach for over a month now.

Any answers here? Does the SWG completley eliminate those chlormaine odors or can they still occur??

Thanks in advance and again, I apologize if this has been answered before in the forum.

Lemmiwinks
09-21-2006, 08:54 PM
I've never posted before, but I have a decent understanding of chemistry in general. Nitrogen waste in your pool will bind with free chlorine to make a chloramine. Nitrogen can come from skin, urine, sweat, fertilizer, etc. I don't think that it matters where the chlorine comes from initially.

chem geek
09-22-2006, 12:52 AM
Lemmiwinks is correct about chloramines getting formed from any source of chlorine, so the SWG isn't any different about that. In fact, the continual dosing and "super-chlorination" in the cell itself (which has around 80 ppm chlorine between the plates) is supposed to keep your combined chlorine (CC) level around zero at all times (you can get pretty darn close to that with liquid chlorine as well, but need to really stay on top of your maintenance).

I suggest you use a FAS-DPD test kit to test for combined chlorine (CC). I suspect, however, that you will find it to be zero or certainly less than the one drop resolution of 0.2 ppm.

A salt pool will outgas chlorine gas from your pool more than a non-salt pool would. In fact, all else equal and at normal levels, a non-salt pool will lose up to 0.3% of it's chlorine per day from outgassing while a salt pool (due to the higher levels of chloride ion) will lose up to 3% or 10 times as much. In addition, an SWG system aerates the water with many tiny bubbles of hydrogen gas coming out of the returns and this also increases the rate of outgassing. So I suspect that your wife is smelling the "clean" smell of regular chlorine, just as if you took a diluted whiff of bleach. If she were smelling chloramines, they would smell "bad" and not like the regular smell of bleach.

In fact, you might try a couple of experiments. First, have your wife sniff around an area of the pool far away from the returns. Then have her sniff near one of the returns. If she smells more chlorine, then the increased aeration is helping to outgas more chlorine.

It is also possible that your SWG is turned up too high in power so that the chlorine generation is too fast to get dissolved fully into the water. If this is the case, then you can try lowering your power level and increasing your "on" time (to get the same net chlorine generation) to see if this reduces the smell around the returns.

If you do either of these experiments, please let us know the results.

Richard