Pool Pilot error message: "warning check/clean cell"

[cscannon]

I have had a pool pilot digital for six years. I replaced my first cell about three years ago. This spring I keep intermittently getting a "warning check/clean cell" message. I have washed the cell with water and have soaked it with acid as recommended in the user manual. The cell looks clean to me.

There is no authorized service in my area. Tech support wants me to send them the cell and the power supply. In addition to the expense of the electrician, shipping, their bench fee, etc., pulling the power supply and the cell leaves me with no way of running the pump until I get the whole thing back!

My salt is 3400, temp 65 degrees, SC-48, Power level 2, volts 28, amps range from 3.4 to 3.8. I know that my amps are low and my volts are high but haven't been able to get a satisfactory answer from tech support as to what causes that.

Anyone have any suggestion?

Thanks,

Steve

[Poolsean]

Have you had the salt level verified? Usually when the water temperature falls around 65 degrees or lower, the SC-48 cell will give you this warning due to the combination of the water temp and low salt levels. My guess is that the salt is low and needs to be calibrated, in conjunction with the cooler water temps and there's a chance that the cell may be wearing out too.
Do the two outer blades in the cell appear to be shorter than the blades between them?

IF your salt level is low, calibrate the salt display to match your test results, then add enough salt to get your level up to 3500 - 4000 ppm. This will compensate for the reduced conductivity in the water from cold water temps, and/or low salt levels.

Keep up posted.

[cscannon]

Thanks for your help. That was certainly part of the problem. I added 160 lbs of salt which was all I had (30k gal pool) and that got the salt level up to 3700 on the test strips I bought. I'll buy some more salt next time I am out.

Curently I am pulling 4.2 amps at 28 volts and 66 degrees, so better but...


What is the significance of the two outer blades in the cell appearing to be shorter than the blades between them? My outer blades are maybe 2 or 3 mm shorter on each side than the others. Is this a sign of age?

How long are these cells supposed to last?

I see that when you replace the cell, there is a menu option that resets the "amp-hours". How does one check the amp-hours on the cell?

Finally, does it wear the cell prematurely to run it at lower temps? I'd rather use bleach during the spring startup and last cool days before closing the pool in the fall if it'd save my cell.

Thanks,

Steve

[Poolsean]

Thanks for your help. That was certainly part of the problem. I added 160 lbs of salt which was all I had (30k gal pool) and that got the salt level up to 3700 on the test strips I bought. I'll buy some more salt next time I am out.

Curently I am pulling 4.2 amps at 28 volts and 66 degrees, so better but...


What is the significance of the two outer blades in the cell appearing to be shorter than the blades between them? My outer blades are maybe 2 or 3 mm shorter on each side than the others. Is this a sign of age?
Yes, the outer blades wear almost in conjunction with the erosion of the ruthenium oxide coating on the blades.

How long are these cells supposed to last?
The cells are suppose to last about 10,000 hours of operation. For 12 month swim seasons, this usually comes out to 3-5 years.

I see that when you replace the cell, there is a menu option that resets the "amp-hours". How does one check the amp-hours on the cell?
The AMP-HOURS display is shown on the TEST POOL PILOT in the MAINTENANENCE MENU, rather than the normal test pool pilot menu option. To reset the counter, it is in the Maintenance Menu under, REPLACE CELL. Press and HOLD the SELECT button for about 8 seconds (or it may be 13 seconds...I don't recall).

Finally, does it wear the cell prematurely to run it at lower temps? I'd rather use bleach during the spring startup and last cool days before closing the pool in the fall if it'd save my cell.
The cell does wear prematurely, but with the TEMPERATURE COMPENSATION feature, it will reduce the output setting automatically so as to lessen the impact of cold water operation.

Thanks,

Steve

I hope I embedded my answers to your questions correctly.

[cscannon]

Thanks. BTW, one of the main reasons that I bought a pool pilot is that I noticed that you or someone else (I don't remember who) was always quick to provide good answers to questions. Keep up the good work!

One last question. Am I correct in remembering that when the cell needs to be replaced I will get a message to that effect?

Thanks again,

Steve

[Poolsean]

You should get a message that says LOW AMPS/CELL?.
At that point, if you verify that your salt level is at least 3000 ppm, the cell is clean, and water temperature is at least 75 degrees, THEN run a TEST POOL PILOT to see where the Cell Amps and Volts are. The normal operating range is 24- 28 volts, and the amperage depending on the Cell Power setting; Cell Power 1 = 5.0 amps, Cell Power 2 = 6.5 amps, Cell Power 3 = 8.0 amps.

Perform a visual inspection of the two outer blades too. These will wear in relation to the cell life by getting eroded on the leading edges of the blades.

[isamisis]

I bought and installed an AutoPilot DIG-220 in 09/24/2006. I chose the cell size of SC-48. I had to replace the SC-48 on 10/26/2009. I monitor the cell monthly and clean if needed per instructions in the manual. I began getting the CHECK CLEAN CELL as well as LOW AMPS/CELL? immediately after the last cleaning. My salt level was low so I added 200 lb. of salt. My salt level has been verified and is at least 3000 ppm. I re-calibrated the salt level on the DIG-220. The cell is clean, I live in AZ and the water temperature is above 75 degrees. I ran a TEST POOL PILOT and the Volts = 17 and the Amps = 3.1/3.2 on Power Level 2. I bought a new cell cord in Oct 2009 when I bought a replacement SC-48. Tonight, I replaced the existing cell cord with the new one when it seemed the salt level was not at fault and the Amps/Volts remained the same (17v/3.1a). I hate to imagine my ALMOST one year old SC-48 is defective when the last cell lasted 3 years. The two outer blades on the SC-48 show no wear. My DIG-220 software version is 4.2. Is another SC-48 purchase in my future?

[CarlD]

Poolsean is very knowledgeable about SWCGs and is always willing to help. We have many people with different expertises, depending on the nature of your pool and the nature of the question.

That's just the way we like it at PF!

[Poolsean]

Don,
I got your e-mail and responded to you there. Feel free to cut and paste my response. If you didn't get it, here's a summary.

The amps and volts should be within a certain range, when operating properly. This is usually either 5.0 amps (cell power 1), 6.5 amps (cell power 2), or 8.0 amps (cell power 3), and the voltage range is based on the cell size:
SC-36 (RC35/22) = 17 -21 volts
SC-48 (RC42) = 21 - 27 volts
SC-60 (RC52) = 20 - 26 volts

As the cell gets worn down or scaled, the water temperature gets cold, or the salt level drops, the voltage will increase to about 28 - 29 volts, at which point the amperage will drop. The SC-36 cell will usually start dropping the amperage at around 25 volts (instead of 29).
So, with the volt increase/amp decrease AND the visible physical erosion of the edges of the terminal blades (these are the two outer blades, and with the SC-60 the center blade too), these two conditions indicate a worn out cell in need of replacement.

The amperage should be consistent with the Cell Power setting and may deviate about 5%.

When the amperage AND voltage are both lower than the normal range, it indicates either that the incoming voltage is not matched to the voltage setting on the circuit board, or there's a power module failure.
Unmatched voltage: The circuit board comes from the factory set for 220 volts. If there is only 110 volts to the board still wired for 220 volts, you would see the volts and amps running at about half the normal range. This is more common with new installations.
This can occur with older 220 volt installations due to a bad circuit breaker sending just one leg of power to the Pool Pilot, that is, 110 volts to a 220 volt wired circuit board.
Bad circuit board: Once you've tested and adjusted everything else (clean cell, correct salt level, water temperature above 75 degrees) and have verified the voltage is correct, then it's usually a bad power module (PN# 16084).