My Zodiac LM2-24 SWG recently (last 2 weeks or so) stopped generating chlorine. There is no chlorine at all in my pool. Across the top of the control panel the indicators are as follows from left to right: Chlorine Output glows amber; Super Chlorinate is green, Add Salt is amber, but my salt reading is 5,000 ppm and the manufacturer's manual recommends a minimum of 4000 ppm, and the No Flow light is red, although the pump is working fine. Both the salt and the chlorine readings came from a test at the local Leslie's Pool store. Also, pressing the on/off button doesn't do anything. In the past when this happened I could clean the cell using diluted muriatic acid to get rid of the calcium buildup and that would fix it. No luck this time. The cell is 3 years old. Any suggestions are greatly appreciated.
Problem With Zodiac LM2-25 SWG
- Thread starter lblomq
- Start date
- Jan 4, 2016
- 5,289
- Pool Size
- 44000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
Welcome to TFP! Good to have you here 
Check out the link in my signature below - "Read before posting". There's some suggestions there that will help you get the best possible advice. For example, if I saw that you had a variable speed pump, I might ask what speed you use for chlorinating, given that your SWC is telling you that there is inadequate flow. If it's a single speed pump, then it may need the flow switch to be fixed. Another possibility is that your water is too cold, but it seems a bit early for that.
I don't want to overwhelm you, but if you're getting scaling on your SWC, your water is very likely out of balance. The first step towards getting your water into balance is some reading, and ordering a reliable test kit. This article describes Trouble Free Pool Care really well: TFPC for Beginners
Check out the link in my signature below - "Read before posting". There's some suggestions there that will help you get the best possible advice. For example, if I saw that you had a variable speed pump, I might ask what speed you use for chlorinating, given that your SWC is telling you that there is inadequate flow. If it's a single speed pump, then it may need the flow switch to be fixed. Another possibility is that your water is too cold, but it seems a bit early for that.
I don't want to overwhelm you, but if you're getting scaling on your SWC, your water is very likely out of balance. The first step towards getting your water into balance is some reading, and ordering a reliable test kit. This article describes Trouble Free Pool Care really well: TFPC for Beginners
Re: Problem With Zodiac LM2-24 SWG
Thanks for the replies. I had created a signature before I posted but guess it didn't save. I also see the typo in the title. It should have been LM2-24, not 25. Here are my test readings:
FAC: 0
TAC: 0
Salt: 5000
CYA: 80
TA: 80
pH: 7.4
Copper: 0
Iron: 0
Pho: 200
Temp: ? I don't have a thermometer
Thanks for the replies. I had created a signature before I posted but guess it didn't save. I also see the typo in the title. It should have been LM2-24, not 25. Here are my test readings:
FAC: 0
TAC: 0
Salt: 5000
CYA: 80
TA: 80
pH: 7.4
Copper: 0
Iron: 0
Pho: 200
Temp: ? I don't have a thermometer
My SWG has been showing the low salt light since the water dropped below 74 or 75 degrees Fahrenheit. The sensor is temperature dependant to some degree when measuring conductivity of the water to calculate the salinity. I usually turn off my SWG when the water gets below 70 and switch to bleach. I may just do it a little earlier this year rather than trying to figure out what is going on with the salt. SWGs are often a little temperamental with lower water temps and will eventually shut off anyway once water gets into the 60s.
Cleaning the cell with muriatic acid will shorten the life of the cell, especially if there is no visible scale build up present. I haven't cleaned my cell in 5 pool seasons.
To prevent scale in your pool and your SWG cell keep your CSI slightly negative, -0.3 to 0. PoolMath will give you the number, tweak TA and pH to move the number. You probably want your TA between 50 and 60 and pH around 7.8. More here, Pool School - Calcium Scaling and here, Pool School - Water Balance for SWGs
Cleaning the cell with muriatic acid will shorten the life of the cell, especially if there is no visible scale build up present. I haven't cleaned my cell in 5 pool seasons.
To prevent scale in your pool and your SWG cell keep your CSI slightly negative, -0.3 to 0. PoolMath will give you the number, tweak TA and pH to move the number. You probably want your TA between 50 and 60 and pH around 7.8. More here, Pool School - Calcium Scaling and here, Pool School - Water Balance for SWGs
I'll read that information, thanks. I don't have visible scaling in my pool. It only accumulates in the salt cell. Last winter I had no issues with the cell generating chlorine all season long so I'm suspecting the cell is bad.