How to trick Hayward TCELL15 that Salt Level is fine?

[BoxfordPool]

I have seen several posts @caliskier about adding a Resister to the blue and black wires inside your TCELL to tell the control panel the Temperature and Salt levels are fine. My TCELL940 (extended life, yeah right) is only 1 year old, but started saying "Low Salt" suddenly, but I tested water and know salt level is good, so Thermiser inside TCELL must be bad. I did get a warranty replacement and all working fine again, but I don't want to toss the bad tcell thinking it should have plenty of life left but for the bad thermister. I do not run in cold weather and maintain salt levels, so I would be happy to bypass the thermister and trick it into thinking salt levels are fine and temp is fine if I can get a few more years of life out of it.

Can someone please post step-by-step instructions on how to add a Resister, link to product to order, how to install, etc? I'm no electrician but pretty handy, just need directions.
Thanks!

 

[ajw22]

Buy a 10K resistor on Amazon and connect it to the red & blue wires. Your challenge is cutting the cable jacket to expose the red & blue wires and then weatherproof the connection.

Good luck.

There are 6 wires, red, blue, 2 black & 2 white. Each black wire powers 1/2 of the cell plates and the white wires are common. Red & blue go to a thermistor inside the cell housing.

Holding the plug vertically with the cord going down and looking at the connection points. 1 is top left, 2 is top right, 3 is second down left and so on with 9 being lower left and 10 being lower right.

1) Black - Power to cell
2) White - Power to cell
3) Black - Power to cell
4) White - Power to cell
5) Brown - Not used
6) Red - Goes to thermistor
7) Orange - Not used
8) Yellow - Not used
9) Green - Not used
10) Blue - Goes to thermistor.

To test the thermistor test between points 6 and 10 using a multimeter, the resistance should follow a 10k thermistor chart.

 

[mas985]

I have seen several posts @caliskier about adding a Resister to the blue and black wires inside your TCELL to tell the control panel the Temperature and Salt levels are fine. My TCELL940 (extended life, yeah right) is only 1 year old, but started saying "Low Salt" suddenly, but I tested water and know salt level is good, so Thermiser inside TCELL must be bad.

Does the cell temperature read differently than the water temperature in the diagnostics menu? Low salt can also mean a dirty cell. What does the inside look like?

 

[BoxfordPool]

Does the cell temperature read differently than the water temperature in the diagnostics menu? Low salt can also mean a dirty cell. What does the inside look like?

Super clean inside, had just cleaned a few weeks prior to the low salt readings. I hadn't noticed the diff in temp, will have to reconnect and see.

 

[BoxfordPool]

Buy a 10K resistor on Amazon and connect it to the red & blue wires. Your challenge is cutting the cable jacket to expose the red & blue wires and then weatherproof the connection.

Good luck.

There are 6 wires, red, blue, 2 black & 2 white. Each black wire powers 1/2 of the cell plates and the white wires are common. Red & blue go to a thermistor inside the cell housing.

Holding the plug vertically with the cord going down and looking at the connection points. 1 is top left, 2 is top right, 3 is second down left and so on with 9 being lower left and 10 being lower right.

1) Black - Power to cell
2) White - Power to cell
3) Black - Power to cell
4) White - Power to cell
5) Brown - Not used
6) Red - Goes to thermistor
7) Orange - Not used
8) Yellow - Not used
9) Green - Not used
10) Blue - Goes to thermistor.

To test the thermistor test between points 6 and 10 using a multimeter, the resistance should follow a 10k thermistor chart.

So can I simply cut the Blue and Red wires inside the TCELL cap cover, and then place a 10K resister between them, basically connecting them together through the resister? Also how do I connect the resister to the wires? Do I just twist connect wires to resister, or does it need to be soldered together, or use some type of connecter? Thanks for your help!

 

[ajw22]

So can I simply cut the Blue and Red wires inside the TCELL cap cover, and then place a 10K resister between them, basically connecting them together through the resister?

That is the idea.

Also how do I connect the resister to the wires? Do I just twist connect wires to resister, or does it need to be soldered together, or use some type of connecter?

Which do you think will give a stable reliable connection in the outdoors?

 

[gkw4815]

What temperature is the thermistor reading? Are you sure it's reading high?

I used a 10k resistor to bypass failed thermistor in my Pureline cell (knock off Hayward cell, was reading 143 degrees water temp).

In my case, I didn't have to cut the salt cell cable jacket or anything like that. Just popped trim cover off salt cell that covers wire going into cell, cut red and blue wires inside, and spliced in 10k resistor. Plenty of room for the resistor and wiring under the cover.

Not sure if it's necessary, but I soldered the resistor in place. Repair was only done a few weeks ago, but so far so good.

 

[C0d3Sp4c3]

Cutting either the blue or red wire will lock the controller temp at 77°F. Unless you want to experiment using a variable resistor. You can verify this by disconnecting the cell from the controller and running the diagnostics. Nothing you can do to bump the conductivity of the cell if the precious coating on the plates is depleted.
Otoh, the resistor will tweak the temp reading but has very little effect on the salt reading. A lower temp will slightly raise the instant salt reading. A 13.3k+/-% resistor will equate to 64-65°F. At 63°F the chlorine production is scaled by 20%. So there's that!

 

[JamesW]

cut red and black wires inside

Red and Blue.

 

[BoxfordPool]

What temperature is the thermistor reading? Are you sure it's reading high?

I used a 10k resistor to bypass failed thermistor in my Pureline cell (knock off Hayward cell, was reading 143 degrees water temp).

In my case, I didn't have to cut the salt cell cable jacket or anything like that. Just popped trim cover off salt cell that covers wire going into cell, cut red and blue wires inside, and spliced in 10k resistor. Plenty of room for the resistor and wiring under the cover.

Not sure if it's necessary, but I soldered the resistor in place. Repair was only done a few weeks ago, but so far so good.

Thank you, I will give this a try!

 

[BoxfordPool]

Cutting either the blue or red wire will lock the controller temp at 77°F. Unless you want to experiment using a variable resistor. You can verify this by disconnecting the cell from the controller and running the diagnostics. Nothing you can do to bump the conductivity of the cell if the precious coating on the plates is depleted.
Otoh, the resistor will tweak the temp reading but has very little effect on the salt reading. A lower temp will slightly raise the instant salt reading. A 13.3k+/-% resistor will equate to 64-65°F. At 63°F the chlorine production is scaled by 20%. So there's that!

Thanks for the info, but I am confused so a few questions please. My problem is tcell says low salt reading, which is false. So my understanding is adding the resister is to set temp and fix the low salt reading, is that right? If the resister will not fix low salt reading then what is the fix?

I cannot imagine my plate coating is depleted when this is a 1-year old 940 extended life version.

 

[JamesW]

Is the temperature reading correct or not correct?

Cell Diagnostics.​

Pressing the diagnostic button sequentially will display:

• Default salt display
• Pool temp
• Cell Voltage - When not generating, the voltage is about 30 to 32 volts dc. When generating, the voltage drops about 1 volt per amp of current.
• Cell current
• Desired output (% of the knob)
• Instant salinity
• Product name
• Software revision (r.XX)
• Cell type

 

[JamesW]

Basic AquaRite Diagnostics.​

This is the basic information we need to know in diagnosing a problem:

• Report all diagnostic readings when you..
  • Move the switch from auto to off and check all of the readings.
  • Move the switch back to auto and recheck the readings.
  • Move the switch to off for a minute and then back to auto and recheck the readings.
• What are the first seven characters of the cell and box serial numbers?
• What is the actual salinity and how are you measuring it?

 

[JamesW]

You can cut the red and blue and connect them to an external temp sensor.

Hayward GLX-PC-12-KIT Replacement Water/Air/Solar Temperature Sensor​

 

[mas985]

Thanks for the info, but I am confused so a few questions please. My problem is tcell says low salt reading, which is false. So my understanding is adding the resister is to set temp and fix the low salt reading, is that right?

Only if that is really what is wrong with the unit. Low salt can be due to many things:

1. Low salt
2. Failing cell
3. Dirty cell
4. Bad temperature sensor
5. Bad solder joint on main board

If the resister will not fix low salt reading then what is the fix?

I cannot imagine my plate coating is depleted when this is a 1-year old 940 extended life version.

More troubleshooting is required to narrow down the problem. There have been many posts to read the cell temperature but so far you have not.

You have a ProLogic correct?

Prologic won't auto-start/stop Heater

Started pool this season and everything working just fine except heater. It fires-up just fine when manually selecting Mode=Pool, but the Prologic is not auto-starting the heater when the Pool Temp is below the set temp. Pool heater settings all look normal on prologic, set to auto-control...

www.troublefreepool.com

In the diagnostics menu, it will show the cell temperature. If that is within 1-2 degrees of the water temperature, the sensor is fine. If it is really high, then yes, the resistor is a fix.

 

[BoxfordPool]

Only if that is really what is wrong with the unit. Low salt can be due to many things:

1. Low salt
2. Failing cell
3. Dirty cell
4. Bad temperature sensor
5. Bad solder joint on main board

More troubleshooting is required to narrow down the problem. There have been many posts to read the cell temperature but so far you have not.

You have a ProLogic correct?

Prologic won't auto-start/stop Heater

Started pool this season and everything working just fine except heater. It fires-up just fine when manually selecting Mode=Pool, but the Prologic is not auto-starting the heater when the Pool Temp is below the set temp. Pool heater settings all look normal on prologic, set to auto-control...

www.troublefreepool.com

In the diagnostics menu, it will show the cell temperature. If that is within 1-2 degrees of the water temperature, the sensor is fine. If it is really high, then yes, the resistor is a fix.

Thanks, I will connect the bad unit and share the temp and other readings.

 

[BoxfordPool]

Ok I noted the Diagnostics readings on my Prologic Diagnostics display panel of the current/new/working TCELL940, and then installed the old/bad TCELL940 to capture same readings:

New Working SWG:
-24.35V
-6.38A
77 degrees
3400 PPM
Cell Temp Sensor: 77 degrees
Water Sensor: 77 degrees

Old/Bad SWG:
+26.09V
+3.22A
75 degrees
1300 PPM
Cell Temp Sensor 75 degrees
Water Sensor 77 degrees
Multi-meter on 6 & 10 plug points: 10.6K ohms

Looks like the Volts and Amps on the Old/Bad SWG are off from normal, and positive vs. negative? Does this help troubleshoot, or anything else I can test?

Thanks again in advance, this forum is awesome and super helpful, greatly appreciated.

 

[mas985]

The lower current on the bad cell points to either a dirty cell or a cell with degraded plates.

The temp sensor looks fine and not the issue.

 

[BoxfordPool]

The lower current on the bad cell points to either a dirty cell or a cell with degraded plates.

The temp sensor looks fine and not the issue.

Interesting. What I find really odd is this is an Extended Life 940 version, and only one year old. It was working fine and should last much longer than one year. The reading dropped suddenly from 3200 to 1600 one day, vs. slowly degraded over time. I had recently cleaned it with acid/water mix per instructions. Here are pics of the plates. Maybe just a bad unit and throw in the trash and hope new one lasts, or do you think there is any life left in this thing?

 

[mas985]

Isn't the cell still under warranty? Contact Hayward and file a claim.

What was the dilution ratio of the acid when you cleaned the cell? I never use more than 10:1 or 3% acid.

Worn cells are not totally worthless. I have been using one for the past year after the unit shut down for low salt:

Failing T-15 SWG Cell Experiment

I am currently on my 3rd T-15 SWG cell for an 18 year old pool. The 1st cell lasted about 9 years and the 2nd about 4 years and just passed year 4 on the 3rd cell. I thought it might be useful to document this cell's behavior as it is going through the last stages of useful life. As time goes...

www.troublefreepool.com