Brand new Jandy PLC1400 stuck on "Cell Reversing"

[Trod760]

UPDATE: Cell Reversing is a non issue, normal cycle. Must've had an algae bloom that was eating up my chlorine.

Recently replaced my 6 year old salt cell with a brand new Jandy PLC1400. Hadn't checked the pool since last week, went out this afternoon and saw the water was cloudy. Checked chlorine levels and, zero point zero. Anyway, the Aquapure control center says the cell is reversing. The cell is clean, verified good voltage hitting the cell and that the sensors were clean. It's dark out now, so I plan to troubleshoot first thing tomorrow morning. My new cell came with a new sensor and power cord, but I didn't install them when I replaced the cell. I'm going to try that first thing tomorrow morning. Just hoping someone here could maybe suggest other troubleshooting tips. In the meantime, I dumped a couple gallons of liquid chlorine in the pool to clear it up. Thanks in advance!

 

[PoolGate]

What % is the cell running? They can stay on reversing for quite some time. Have you done an OCLT? With no errors on the panel, it is likely your cell is producing chlorine. It might just be used up before you can get a reading. I suggest you put liquid chlorine in until you get this issue sorted out.

Overnight Chlorine Loss Test

 

[Trod760]

What % is the cell running? They can stay on reversing for quite some time. Have you done an OCLT? With no errors on the panel, it is likely your cell is producing chlorine. It might just be used up before you can get a reading. I suggest you put liquid chlorine in until you get this issue sorted out.

Overnight Chlorine Loss Test

I dumped 2 gallons of liquid chlorine in it as soon as I noticed there was an issue. This morning, i replaced the flow sensor and power cable with the new ones that came with my new cell. I put it in boost (100%) about 1.5 hours ago and it still says it's reversing. Not sure what an OCLT is? Would you happen to know how long the cell reversing cycle normally lasts? Is it something that's programmable?

 

[PoolGate]

I dumped 2 gallons of liquid chlorine in it as soon as I noticed there was an issue. This morning, i replaced the flow sensor and power cable with the new ones that came with my new cell. I put it in boost (100%) about 1.5 hours ago and it still says it's reversing. Not sure what an OCLT is? Would you happen to know how long the cell reversing cycle normally lasts? Is it something that's programmable?

The electrolytic cell contains bipolar electrodes which perform the electrolysis and produce chlorine when energized with DC current. Chlorine is generated as pool water containing salt passes through the cell. The chlorine production can be varied by either adjusting the chlorine production level on the power center or by varying the number of hours the unit is on each day. The system automatically cleans the cell’s electrode plates once every 3 hours by reversing the polarity of the electrical current. Whether the system is in forward or reverse, it is still producing chlorine.

https://cdn.fluidrausa.com/-/media/zodiac/global/downloads/h/h0325600.pdf?rev=444148fe01b6479d95808b6396cbe046

 

[Trod760]

Ok, thanks. I was under the impression that during the reversing cycle, it did not produce chlorine. BTW, now been over 2 hours in the reversing stage.

 

[Trod760]

Update. At about the 3 hour mark, cell reversing went away. Thinking i should just go ahead and order a new circuit board for the aquapure center.

 

[jesse-99]

The Jandy PLC700/1400 goes 3 hours before switching to/from forward and reverse. So what you're seeing is normal. if its switching every 3 hours.

 

[generessler]

A new cell getting correct voltage with correct salt must be generating chlorine. Have you tested salt with a Taylor kit? The sensor can easily be off by 300ppm even if correctly calibrated.

Did you measure voltage at the cell? This includes the low voltage cord, so it's the best method.


In general, this cell is marginal for a 36k gal pool. Flat out (100% for 24x7) in "new" condition it generates 1.25 lb of chlorine a day. That's only 4.16 ppm for your pool. So in normal summer conditions losing ~2 ppm a day you'll need 50% for 24 hours a day, 100% for 12 hours, or some combination between.

So what is your CYA? That will make a difference. Best at 70+ for the cell not to be overwhelmed. If it's less than 60, it will struggle for sure.

From the AquaPure manual, which is worth reading...

The system automatically cleans the cell’s electrode plates once every 3 hours by reversing the polarity of the electrical
current. Whether the system is in forward or reverse, it is still producing chlorine.

 

[Trod760]

A new cell getting correct voltage with correct salt must be generating chlorine. Have you tested salt with a Taylor kit? The sensor can easily be off by 300ppm even if correctly calibrated.

Did you measure voltage at the cell? This includes the low voltage cord, so it's the best method.
View attachment 507631

In general, this cell is marginal for a 36k gal pool. Flat out (100% for 24x7) in "new" condition it generates 1.25 lb of chlorine a day. That's only 4.16 ppm for your pool. So in normal summer conditions losing ~2 ppm a day you'll need 50% for 24 hours a day, 100% for 12 hours, or some combination between.

So what is your CYA? That will make a difference. Best at 70+ for the cell not to be overwhelmed. If it's less than 60, it will struggle for sure.

From the AquaPure manual, which is worth reading...

hello, yes. getting 24 vDC at the cell. My CYA is at 90-ish and I run my pump for 12 hours a day at 80%. I downloaded the jandy workbook and was going to go through all of the voltage checks on the circuit board sometime this week. My old cell could keep up no problem before it died out. If you guys are saying "cell reversing" for 3 hours is normal, then I guess I'll just have to run my pump longer. Can you confirm that the cell does NOT produce chlorine while it's reversing? that would make me feel a littler better. I just spend $1200 on this brand new cell 2 months ago. Also, my pool is less than 13k gallons. so the cell should be able to produce more than enough chlorine for it.

 

[Trod760]

A new cell getting correct voltage with correct salt must be generating chlorine. Have you tested salt with a Taylor kit? The sensor can easily be off by 300ppm even if correctly calibrated.

Did you measure voltage at the cell? This includes the low voltage cord, so it's the best method.
View attachment 507631

In general, this cell is marginal for a 36k gal pool. Flat out (100% for 24x7) in "new" condition it generates 1.25 lb of chlorine a day. That's only 4.16 ppm for your pool. So in normal summer conditions losing ~2 ppm a day you'll need 50% for 24 hours a day, 100% for 12 hours, or some combination between.

So what is your CYA? That will make a difference. Best at 70+ for the cell not to be overwhelmed. If it's less than 60, it will struggle for sure.

From the AquaPure manual, which is worth reading...

hello, yes. getting 24 vDC at the cell. My CYA is at 90-ish and I run my pump for 12 hours a day at 80%. My old cell could keep up no problem before it died out. If you guys are saying "cell reversing" for 3 hours is normal, then I guess I'll just have to run my pump longer. Can you confirm that the cell does NOT produce chlorine while it's reversing? that would make me feel a littler better. I just spent $1200 on this brand new cell 2 months ago.

 

[generessler]

The ~2 ppm loss per day is a normal/average value. It varies with many factors. In particular if you already have an algae bloom in progress (even if you can't see a change in the water), the cell will never catch up. Do an OCLT to determine if that's the case. If the test fails, start a SLAM.

 

[PoolGate]

hello, yes. getting 24 vDC at the cell. My CYA is at 90-ish and I run my pump for 12 hours a day at 80%. My old cell could keep up no problem before it died out. If you guys are saying "cell reversing" for 3 hours is normal, then I guess I'll just have to run my pump longer. Can you confirm that the cell does NOT produce chlorine while it's reversing? that would make me feel a littler better. I just spent $1200 on this brand new cell 2 months ago.

The cell DOES create chlorine in both forward and reverse. I have the same cell as you and a 29k gallon pool. I run my pump 24 hours a day. I keep my cell percent at 53%. This maintains a FC of around 7 in my pool.

This is from Jandy's manual:

The electrolytic cell contains bipolar electrodes which perform the electrolysis and produce chlorine when energized with DC current. Chlorine is generated as pool water containing salt passes through the cell. The chlorine production can be varied by either adjusting the chlorine production level on the power center or by varying the number of hours the unit is on each day. The system automatically cleans the cell’s electrode plates once every 3 hours by reversing the polarity of the electrical current. Whether the system is in forward or reverse, it is still producing chlorine.

 

[Trod760]

Thank you for your help, Sir. I guess I'll just up the run time / % and see what happens.

 

[PoolGate]

Thank you for your help, Sir. I guess I'll just up the run time / % and see what happens.

Are you sure you have the PLC1400 and not the PLC700? They look identical. Your pool size I would be surprised if your builder put the 1400 series in.

For 12800 gallons:

24 hours/day at 100%:
1400 - 12FC
700 - 6FC

12 hours/day at 80%:
1400 - 4.8FC
700 - 2.4FC

If you bought the PLC1400 cell but originally had a PLC700, you need to make a change to the control unit before it will recognize the cell as a 1400 series.

 

[Trod760]

Yes, it's definitely the 1400. Thanks for those numbers. I'll keep an eye on it. Today it held strong at 3.5 - 4ppm all day at 80%. I just re-tested now (3.5) , shut off pump and will check again tomorrow morning before the pump turns back on to see if maybe algae is to blame.

 

[Trod760]

Update:
ran an OCLT as per the instructions. Was at 3.5ppm last night, this morning was at 2.5 which falls into the range of "clean water". Turned the cell back on, waited about 30 minutes, checked chlorine right out of the return and was at 3.5ppm, so the cell is definitely working. Starting to wonder if maybe I just had a sudden algae bloom that killed my chlorine and killed it off when i dumped the 2 gallons of liquid chlorine in it when I noticed the cloudy water. Going to run the cell for 16 hours instead of 12 and see where I'm at in a few days. Thanks for all your help, guys. Gonna familiarize myself with all the jandy documentation on my equipment.

 

[generessler]

In general, this cell is marginal for a 36k gal pool. Flat out (100% for 24x7) in "new" condition it generates 1.25 lb of chlorine a day. That's only 4.16 ppm for your pool. So in normal summer conditions losing ~2 ppm a day you'll need 50% for 24 hours a day, 100% for 12 hours, or some combination between.

Hey I'm sorry I looked sideways at @jesse-99 's pool size and thought it was yours. For your pool, the PLC1400 is absolutely fine. At 12800 gallons, the 1.25 pounds per 24 hours is 11ppm! 12 hours at 80% is 4.6 ppm per day. That's not impossible, but at the high end of normal for daily consumption. Maybe exactly right for Palm Springs. Otoh, the marginal OCLT plus this may indicate some low level algae. I defer to experts, which I'm not.