chemical smell when running jets

[Marcie]

Have Cameo tub and recently when running jets there is a chemical smell that makes me cough. Not there when the jets are not running. We have ozone and use Renew. Any thoughts?

[Marcie]

Sundance spa, Cameo model. Thanks

 

[RDspaguy]

How long since you changed your water? The jets agitate and aerate the water an could cause odors you might not notice when the water is calm. Chemical residue and sanitization byproducts build up in the water over time.

Detail your chemical maintenance routine.

@waterbear, any ideas?

[waterbear]

Renew is a non chlorine shock by Leisure Time  which means you are either using bromine or chlorine since it is not a sanitizer on it's own and is used in conjunction with other chemicals. Which is it, chlorine or bromine? Both can produce a chemical smell when things are not right but for different reasons. Please post a full set of test results NOT done with test strips and we can take it from there. FWIW, Ozone can also cause coughing if it is building up under the cover and not allowed to dissipate by running the spa for several minutes before going in or by a malfunction or maladjustment of certain types of ozone generators. Is yours UV or corona discharge?

[JoeTee]

Hello, I do not mean to hijack this thread, but I am experiencing the exact same issue.  I get in the tub and the water is perfect, no smell and crystal clear.  I turn on the jets and I get what I think is a terrible chlorine/chemical smell.   Some background...I have a 6 month old Jacuzzi 300 series with UV and Ozone, and I am sanitizing with chlorine (Spa Boss Chlor-Aid).  This is my first hot tub, so I am not sure if this is normal, but it does not seem right.  I have done several flushes and water changes in the 6 months of ownership..most recently a few days ago, and I still get the smell when I turn on the jets (no smell at all when the jets are off).  Here are my parameters after a fresh fill;

Total Alk - 63
Calcium Hardness - 60
PH - 7.5
Free Chlor - 2.25

The tub gets used every few days by 1 or 2 people for 15-20 minutes.  I typically add 1 tsp of Chlorine per person after a soak, which keeps the level between 1-3 ppm, and I add 1/2 cup of MPS shock once a week.  I leave the cover open and run the jets for 5 mins after adding.  The circ pump/ozone/uv runs for 10 hours a day. 

My dealer recommends using Spa Marvel water treatment, so I used that for the first 2 fills, but it seems expensive so I have not used if for the past 2 refills.  I do use the Spa Marvel cleanser to flush before a refill.

Any input would be greatly appreciated. 

Thanks
Joe

 

 

 

 

[waterbear]

19 hours ago, JoeTee said:

Total Alk - 63
Calcium Hardness - 60
PH - 7.5
Free Chlor - 2.25

Looks like dealer testing with strips and a machine to read them. There is no mention of either total chlorine or combined chlorine which are important since combined chlorine can produce a chemical or chlorine smell while free chlorine does not smell. Ozone also has a smell and can build up in a covered tub. Does the smell dissipate after running the jets for 5 minutes or so? If it does then I wouldn't lose any sleep over it as long as you test for combined chlorine and it is no higher than .5 ppm. I would also recommend investing in a good test kit (Taylor K-2006, don't get the K-2005) and start testing your own water! It might seem expensive but consider how much the kit costs vs the price you paid for your spa! It's the best investment you can make. Also read this:

https://www.poolspaforum.com/forum/index.php?/topic/23090-dichlorbleach-method-in-a-nutshell/

 

[JoeTee]

Thanks for the reply, waterbear.  I purchased the Lamotte ColorQ 2x Pro, and have been testing with that.  It does test for Total Chlorine, but the results are not accurate due to my use MPS Shock (this was confirmed from their tech support).  Maybe I will invest in the K-2006 to compare the readings.

As for the smell, it does dissipate a little after running the jets, but it is still there.  it's just funny that the water does not small at all before I turn on the jets...even if I splash it around.  it just seems odd that it happens even after a fresh fill (about a day after adding chlorine).

in the back of my mind I have this feeling that there is something in the plumbing..microfilm maybe, and that is causing the smell.  But I have never let the water go foul, so I sent know if biofilm could have built up in such a short time.  but my lack of experience could prove that theory to be wrong.  I'm considering trying a flush with Ahh Some and see if anything comes out.  

 

 

[waterbear]

Taylor make an add on fro the K-2006 to remove the interference from MPS but the easiest way is to stop using MPS and shock with liquid chlorine (plain unscented laundry bleach without thickeners or other additives at either 5.24% or 6% sodium hypochlorite. Janitorial Clorox or a house brand is best, Retail Clorox contains an additive to keep dirt from depositing back on clothes in the wash but this same chemical is also the active ingredient in many pool and spa water clarifiers so it should not present a problem.

The LaMotte chemistries has some limitations. Its tests are colormetric and, while precise, are not as accurate as the titration tests (drop counting) used by Taylor. Precision is not the same as accuracy.  Accuracy refers to the closeness of a measured value to a standard or known value.  Precision refers to the closeness of two or more measurements to each other.  I used to use the professional LaMotte testing when I worked retail in the industry and was certified by LaMotte in the proper use, limitations, and interactions with their testing procedures. It is designed to be easy and fast and pecise (repeatable results  on repeated testing of the same sample) but not necessarily accurate (results having a very narrow margin for error) some of the tests only give accurate results within a very narrow range and if your water is out of that range the rsults are going to be off, sometimes significantly. The main advantage to LaMotte's testing (especially for pool stores and pool service personel) is that the tests are very fast compared to the more accurate Taylor tests.

[RDspaguy]

I could see how, theoretically, a biofilm could cause combined chlorine inside the pipes while the pump is not running. Then, when you move that water out of the pipes it might release some odor. Theoretically. Maybe...

[JoeTee]

Well...I just received my new K-2006 test kit, and I ran 2 chlorine tests using the FAS-DPD method.  Both came back with FC 9.0 (45 drops x .2 using 25ml of water) and CC .6 

I ran a test with my Lamotte ColorQ 2x and it said FC was 1.75.    I dug up the test strips that came with the tub 6 months ago, and sure enough they are matching more closer to the Taylor at 9'ish (they are so hard to read). I'm shocked that the Lamotte is that far off??

So, if the Taylor test is correct, I have been WAAY over chlorinating my hot tub!  Maybe this is causing the chemical smell??

 

[RDspaguy]

Ding! Ding! Ding! We have a winner! Let us know how it goes from here.

[waterbear]

ColorQ used DPD testing and their reagents can bleach out at FC levels above 5 ppm! Tayor DPD (K-2005) is good to about 10 ppm and if it is bleaching out there are instructions on how to dilute your sample. Taylor FSD-DPD (K-2006) will work up to about 20 ppm if you add an additional scoop or twp of DPD powder. Use a 10 ml sample instead of the 25 ml sample, then one drop of reagent is .5 ppm of chlorine use 25 ml samples with the TA and CH tests.

With either Taylor FC/CC test you can tell if it is bleaching out vs no chlorine present easily. IF the color  flashes pink as you add the reagent (liquid in the K-2005, powder in the K-2006) and then goes clear it is bleaching out due to high chlorine levels. IF it never goes pink and stays clear then you have no chlorine present.

[JoeTee]

So, the saga continues...I have used the spa for three 20 minute soaks since yesterday's first test with the K-2006 showing 9.9 ppm FC, and have not added any Chlorine or MPS.  Since yesterday I have been performing several test using the K-2006, the ColorQ 2x, and 2 different brands of test strips, and even an trip to my local pool store for a test.

The Taylor is still reading very high FC, an average of about 9.0 ppm using both 25 and 10ml tests...I say "about", because it's easy to loose track when adding 40-50 drops to the sample!  I'm really trying to trust the Taylor kit, however, I've been steadily watching FC levels slowly drop (which I would expect) on all my tests using the ColorQ and both brand test strips.  The ColorQ currently shows .2 ppm FC, and the test strips indicate just about no FC.  I took a sample to my local pool store and they did a test with the Lamotte Spin Touch and it said .21 ppm FC (pretty damn close to the ColorQ).

I called Taylor and spoke to a technician to verify I am doing everything right.  Very nice guy, and we chatted for a while and it sounds like I am doing everything right. He check the lot #'s on the reagents and said they are only a month and a half old, so essentially brand new.   At this point, I am having a hard time believing the Taylor kit is accurate.  I can't help but to think maybe I have a bad batch of FAS-DPD reagents?  But here's the kicker...I did a 25ml test on my city tap water, and it reads .4 ppm FC, which tells me the kit is working.

Very frustrating...any input or advice would be greatly appreciated.

For what's it's worth, the spa did not have any chemical odor when I was just in it  

-Joe

 

[JoeTee]

I've been searching this forum, and I found an old post from @chem geek which said;

"MPS can show up as FC and not CC if you are using a FAS-DPD test and there is any chlorine at all.  So yes you can use a test kit, but it would be the Taylor K-2006 or equivalent with a FAS-DPD test and then you should get the Taylor K-2042 MPS interference remover that will let you test for FC, CC, and MPS separately."

I was under the impression that MPS effects CC readings, but from what Chem Geek is saying, MPS effects FC readings when using FAS-DPD test.  So maybe that is why I am seeing such a high FC reading??

 

 

[RDspaguy]

I've heard it can throw off other readings as well. I don't personally know, as I don't even own any mps myself.😉

[ratchett]

8 hours ago, RDspaguy said:

as I don't even own any mps myself.😉

Ozonator's for the win! haha

[waterbear]

MPS can affect both FC and CC. Believe the Taylor kit. There is NO reason to use a 25 ml sample for the FAS-DPD test. Use the 10 ml sample. Also use a10 ml sample for the CH test if your CH is very high (above 300-400 ppm unless you really LOVE counting drops! At CH levels that high a precision of .25 ppm is more than enough. Did you get the Taylor MPS interference remover add on for the K-2006? IF not pick one up. They make it in 2 sizes, one with .75 ounce reagents that will fit into the K-2006 box (K-2141) and with 2 oz. bottles of reagent that fit the Service complete kits (K-2142).

IF you want to verify that total chlorine/MPS is high you can pick up a cheap 2 way OTO test kit. These will have a comparator with shades of yellow instead of the red color blocks found on a DPD test. OTO is bulletproof(won't bleach out and will turn yellow if there is chlorine/bromine/MPS present) but it only tests TOTAL sanitizer/oxidizer. My guess it will read off the scale. Taylor has the K-1000 (I use this for quick daily checks and the pH test is wider range than the K-2006 but not as accurate since it has wider color blocks graduation than the Kl-2006 and uses a different pH reagent (R-0014 instead of R-0004). You can usually find cheap test kits with OTO and pH at such places as Walmart, Home Depot, and Lowes but I would not trust the pH tests in these since they are not going to be accurate above 3-5 ppm sanitizer. This includes LaMotte's pH test, btw. The Taylor pH reagents are good up to about 10 ppm sanitizer.

[JoeTee]

@waterbear Thanks for the reply.  I've been trying to find the MPS interference kit, but nobody has it in stock, and will take 14 days to arrive.  So, I decided to start fresh...I did a flush with ahh some, there was some gunk but not too bad.  Drained, refilled, ran jets for 20 mins and drained and refilled again.  On a fresh fill the Taylor worked as expected using 10ml samples for FAS-DPD.  Results on a fresh fill were;

FC-1
CC-0
PH-7.6
TA-50
CalHard-40
CYA-0

Following Nitro's startup procedure, I raised the TA to ~80 (was that really needed, or should I have left it at 50?), added 4oz of cal-rise, and shocked with dichlor to 10ppm.

Stay tuned  

Appreciate all the help.

-Joe

[waterbear]

( would have left it at 50 or 60 The higher the TA the faster pH will rise because of the aeration.

[JoeTee]

...Almost 24 hours later and FC dropped about 4ppm, down to 6ppm.  Ph is now 7.8, so yeah, I probably screwed up adding that 1oz of alkaline-rise.  oh well..I'll sort that out.

One more question...if I stick to the Dichlor/bleach method of sanitizing, do I have to use MPS?  I had been adding about 1/2 cup of MPS every week.  What would be a substitute for MPS?

 

 

[waterbear]

9 minutes ago, JoeTee said:

What would be a substitute for MPS?

You don't need MPS, just chlorine! I The only reason you might need MPS is if you have persistent CC over 1 ppm for about a month. IF shocking with chlorine gets it to .5 ppm or less then you are fine. Uncovering the tub and running it while exposed to full sunlight for about an hour or even less will also help destroy CC (UV light) and if your CYA is in range then you should not get a big chlorine loss from the UV (which is what CYA does, keeps chlorine from being destroyed by UV).

IF your CYA is below 20-30 ppm use Dichlor, it will add approx. 1 ppm CYA for each 1 ppm of chlorine added (CYA is cumulative so once you have added enough dichlor over time to total about 20 -30 ppm your CYA should be in range but test it to make sure. You only use CYA with water changes and refills from splashout. You do not lose it by water loss from evaporation so it is important to test it weekly to monthly, depending on how often the spa is used.

Once you reach a CYA level of 20-30 ppm use Bleach (Sodium Hypochlorite, Liquid laundry bleach with no additives, thickeners, scents, etc. such as Clorox or a store brand in either 6% of 5.35%, Liquid Pool chlorine in either 10% or 12.5%) You don't need MPS at all.

Since this is a fresh fill what is your combined chlorine after shocking, assuming that you have not added any MPS? IF you did you might want to start over with a fresh fill and don't use any MPS. IF your CC is over .5-1 ppm then there is organic matter or biofilm in your tub and you might want to consider a purge and refill. Otherwise I would not be concerned with the 4 ppm FC loss after shocking unless the CC stays at an elevated level for more than one shocking. Bottom line, when CC is above 1 ppm you need to shock with either dichlor or bleach, depending on current CYA level. Once CCYA is at target your shock level is 13-15 ppm FC (in other words, you want to add enough chlorine to raise your CURRENT FC level to 12-15 ppm, IF your CYA is 20 ppm then use 12 ppm FC if it is above 20 ppm and below 50 ppm use 15 ppm FC)

[JoeTee]

Thanks for the info, I just checked and I currently have 0 CC.   I have not used MPS since the refill yesterday, and I will follow your advice and not use it going forward.  

[MCFran]

Hey, thank you all guys, got the same problem with my MCP tub