Jandy AquaPure PLC1400 Salt Cell - Error Code 121

Sep 26, 2018
103
Tampa, FL
Well I think my PLC1400 (just shy of 5 years old) is finally on its last leg... Showing error code 121 (low current in reverse direction to cell). A physical inspection of the inside of the cell does not reveal much... Very minor scaling if any and no damage that stands out... 3,300ppm salt in the pool.

Forward Direction:
5.5 Amps DC (clamp meter)
35.5 Volts DC (measured where cable connects to cell)

Reverse Direction:
2.5 Amps DC (clamp meter)
40.0 Volts DC (measured where cable connects to cell)

I still have chlorine production in the pool and only have the cell set to 30% production... I know it is winter and the pool spends most of the day in the shade this time of year, so I fully expect the demand to increase beyond what this dying cell can handle as we approach spring/summer. Any problem with letting this cell run out until it can't make chlorine anymore? The replacement is going to be a big purchase, so thinking I will let this one run as long as possible?

Also why is my voltage jumping up so high? I remember reading 29-30VDC a few months ago...
 
The controller increases the voltage to try to keep the amperage at the correct level.

Check the cell for scale and clean if necessary.

Check the cord and prongs for corrosion.

Check the plates for signs of corrosion.

No significant amount of scale. Plates look good to me.

Don't really see anything going on with the cord or prongs. I did add dielectric grease to the cord connector/ cell prongs in hopes that would prevent any outside corrosion and make my cell last longer.. Probably a nice thought, but at almost 5 years old, likely too late.

I have not tried unscrewing the plastic plate around the 3 prongs on the cell yet... I also figured the middle prong is probably going bad and was worried if I did this the cell might fully quit on me...

I wonder how long it will last in this crippled state?
 
https://www.polytecpools.com/Jandy-AquaPure-PLC1400-Replacement-Cell-w16-Cord_p_5276.html

https://www.polytecpools.com/Jandy-AquaPure-PLC1400-Replacement-Cell-w25-Cord_p_6757.html


The Jandy PLC1400-25 is used as a replacement cell for existing systems or when purchasing a new PureLink system.

For use on swimming pools up to 40,000 Gallons

This is the new style AquaPure Replacement Cell. This cell replaces old Jandy part numbers R0403500 and PURE1400

*NOTE: Some existing AquaPure's with "A0116500" labeled Union Nut may not work either with cell r-kit #'s R0475300 and R0475400.

If the existing AquaPure union nut does not thread onto the 3-Port, 2" cell properly, it will be necessary to cut out the existing tail pieces and unions and re-plumb using the union nuts and tail pieces included in the r-kits R0475300 and R0475400 (unions included as of June 30, 2008).
 
  • Like
Reactions: JamesW

Enjoying this content?

Support TFP with a donation.

Give Support
I got a cell + cord for $649 from Pool Supply Unlimited. No sensor, but if yours is working okay, there's no need to replace it afaik. Been working fine for 1.5 seasons so far.

(The old one present when we got the house looked to be 14 yrs old based on serial number. But sensor was fried, so no way of saying what working life was. Replaced sensor and it went for another 2 years.)
 
  • Like
Reactions: wakerider017
Can't hurt to call Fluidra(Jandy). If you registered your cell they may replace it even out of warranty. I had a good experience when mine had issues, but I was well under warranty. Worst they can say is no. Worth a shot.
 
  • Like
Reactions: wakerider017
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.