Replaced T-15 with Tcell940 and no Chlorine

Jul 10, 2015
36
Massachusetts
I broke down and finally replaced my 10 year old T-15 With the compatible TurboCell T940 since I had a check cell on a lot last year and never could get it off in the week after open. I proceeded to break the collar coming from my filter and it had to be redone by a pro - an entire saga of 10 days waiting. So the pool has been running and I cleaned all the pollen from the filter and it looks great. Unfortunately the Hayward controller is showing 0 instant chlorine along with 2200 last reading, and the Check Salt and Inspect Cell are on. I bought a salt test kit while waiting for a repair on very good recommendation from this forum. That reads 3400ppm, so it 0 or 2200 from the cell! All instructions say the T940 is compatible and leave the Cell type at T-15. The other chemistry seems within normal after adding Baking Soda and Borax and 12.5% Chlorine. The pump has been running 24/7 for 4 days, but I am pro putting it on the timer tonight. Any ideas on what could be happening?
 
I broke down and finally replaced my 10 year old T-15 With the compatible TurboCell T940 since I had a check cell on a lot last year and never could get it off in the week after open. I proceeded to break the collar coming from my filter and it had to be redone by a pro - an entire saga of 10 days waiting. So the pool has been running and I cleaned all the pollen from the filter and it looks great. Unfortunately the Hayward controller is showing 0 instant chlorine along with 2200 last reading, and the Check Salt and Inspect Cell are on. I bought a salt test kit while waiting for a repair on very good recommendation from this forum. That reads 3400ppm, so it 0 or 2200 from the cell! All instructions say the T940 is compatible and leave the Cell type at T-15. The other chemistry seems within normal after adding Baking Soda and Borax and 12.5% Chlorine. The pump has been running 24/7 for 4 days, but I am pro putting it on the timer tonight. Any ideas on what could be happening?
Did you select Tcell 15 in the aqua rite menu? If that’s not set correctly it can get all wonky like that if it thinks it has a smaller cell in it.

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

  • Report all 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.
 
Did you select Tcell 15 in the aqua rite menu? If that’s not set correctly it can get all wonky like that if it thinks it has a smaller cell in it.

I did. That was the original setting from the old cell and had the Check Cell issue from the start. I fooled with it to change to another cell type, but there wasn’t a T940 setting. After research discovered that Tcell 15 is the correct one so it is set to that again.
 
I did. That was the original setting from the old cell and had the Check Cell issue from the start. I fooled with it to change to another cell type, but there wasn’t a T940 setting. After research discovered that Tcell 15 is the correct one so it is set to that again.
Ok then, see ajw22 post above.
 
Ok three columns so I hope you can help. What I see is it runs for a minute then the Voltage and Current change as the lights fault. I recall soldering a thermistor a few years ago, so maybe it is broken again. :unsure: I will look at the board again tomorrow

order of data is auto to off, off to auto, off a minute wait to auto

Light Setting
power - green, green, green
generating - off, green, green
super chlorinate - off, off, off
remotely controlled - off, off, off
no flow - off, off, off
check salt - off, off then to red, off then to red
high salt - off, off, off
inspect cell - off, off then amber, off then amber

Readings
Salt - 1100, 1100, 1100
Temo - 74, 74, 74
Voltage - 32.5, 32.5 then to 22, 32.5 then to 22
Current - 0, 0 then to 3.3, 0 then to 3.3
Desired Output - 55, 55, 55
Instant Salinity - 0, 0, 0
Product Name - AL-1, AL-1, AL-1
Sortware Revision - r 1.55, r 1.55, r 1.55
Cell Type - T-15, T-15, T-15
 
I don’t think it is a bad thermistor. Symptoms of a bad thermistor include no power and chlorinating light, no power to salt cell.

It looks like you have a bad cell.

But look carefully at the board for burnt solder joints around the K1 or K2 relays.
 
I looked at the board today. Nothing looks burnt out or comes apart at the touch, as the thermistor did when I fixed it before. There was a dense spider web at the part where the flow connector comes in. I cleaned that off in hope it was the issue. It was not as everything returned to the same settings - check salt and inspect cell lights both on. I searched around and found this Hayward trouble shooting guide And think it is the board. Here is the flow chart. I have seen the high Amps and 0 current which says it is the board. I will check again the morning to confirm the settings with the lights on. If anyone has more to check into, please let me know. Here is the link to the trouble shooting guide and the page with flowchart is below as an image. Hayward SWG Troubleshooting

SWG.png
 
You said you get 22V and 3.3 amps on both polarities.

Voltage goes from 32.5 to 22 and amps go from 0 to 3.3.

I am surprised you get the same volts and amps on both polarities.

Check the diagnostics and post is again in three separate lists, not the columns you did.
 
Results below. Just for fun, I put in the cell I replaced to start this project and the same thing is happening with the lights and numbers. Maybe all along it was the board, since I never had scaling but did a wash anyway.

Anyway here are the numbers again. When initially on, the current and amps are in normal range and generating light is on. Then the low salt and check cell lights come on, the numbers are 32.7 and 0

Switch from auto to off
Lights
Power. Green
Generating off
Super Chlorinate off
Remotely Controlled off
No Flow off
Check Salt off
High Salt off
Inspect Cell off

Salt. 0
Temp 75
Voltage 32.4
Current 0
Desired output 56p
Instant Salinity 0
Product name AL-1
Software revision r 1.55
Cell type t-15


Off to auto - when lights on after a minute
Power. Green
Generating off (on for 30 secs)
Super Chlorinate off
Remotely Controlled off
No Flow off
Check Salt red (off for 30 secs)
High Salt off
Inspect Cell amber (off for 30 secs)

Salt. 1100
Temp 75
Voltage 32.7 (initially 22 and fluctuating)
Current 0 (initially 3.3 and bouncing around)
Desired output 56p
Instant Salinity 0
Product name AL-1
Software revision r 1.55
Cell type t-15

Off for a minute
Power. Green
Generating off (on for 30 secs)
Super Chlorinate off
Remotely Controlled off
No Flow off
Check Salt red (off for 30 secs)
High Salt off
Inspect Cell amber (off for 30 secs)

Salt. 1100
Temp 75
Voltage 32.7 (initially 20 and fluctuating)
Current 0 (initially 4. something and bouncing around)
Desired output 56p
Instant Salinity 0
Product name AL-1
Software revision r 1.55
Cell type t-15
 

Enjoying this content?

Support TFP with a donation.

Give Support
@JamesW board or cell?
I put the old cell back into the system to see if it would have a different result on the board. My thinking was the salt WAS low at the start of the season and the cell was 10 years old so it was time to replace. But the results were the same as with the new cell. To me, that says the board is bad. As you or another said, the fuse or thermistor shows different symptoms
 
An update…. I ordered the thermistor from Amazon June 14. It didn’t arrive within a week so I got a refund from Amazon. I decided to continue to use liquid chlorine this season because I was done with this for only 8 more weeks of swim time, and the weather sucks here so never have wanted to use the pool. But the thermistor showed up today. I removed the old one I had replaced about 5 years ago and it was crumbly when I pulled on it, even though it seemed OK to the eye. I was optimistic this was it!!! But when putting the box back, the two lights came on again after the 3 minutes. The instant salt level was 2300, but test kit say 3300. So I will recheck tomorrow after the timer comes back on and also review my soldering. So bummed 🙁 but hope it is my user error.
 
Redo the diagnostic readings.

Report all 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.
 
I rechecked soldering and it was fine. Never wanted it to be a user error more 😁.

Here are the results which are the same. It looks normal for about 30 seconds then the lights come on and the voltage and current change.

I will buy a new board, which may mean I didn’t need a new cell It was 10 years old but looked good since we are running only 18 weeks a year. my mistake for doing it before the pool was fully up and salt tested on a kit.

I also have photos of the new cell.


Switch from auto to off
Lights
Power. Green
Generating off
Super Chlorinate off
Remotely Controlled off
No Flow off
Check Salt off
High Salt off
Inspect Cell off

Salt. 2300
Temp 73
Voltage 32.2
Current 0
Desired output 56p
Instant Salinity 0
Product name AL-1
Software revision r 1.55
Cell type t-15


Off to auto - when lights on after a minute
Power. Green
Generating off (on for 30 secs)
Super Chlorinate off
Remotely Controlled off
No Flow off
Check Salt red (off for 30 secs)
High Salt off
Inspect Cell amber (off for 30 secs)

Salt. 2300
Temp 7
Voltage 32.7 (initially 22.4)
Current 0 (initially 4.18.3)
Desired output 56p
Instant Salinity 0
Product name AL-1
Software revision r 1.55
Cell type t-15

Off for a minute then on

Power. Green
Generating off (on for 30 secs)
Super Chlorinate off
Remotely Controlled off
No Flow off
Check Salt red (off for 30 secs)
High Salt off
Inspect Cell amber (off for 30 secs)

Salt. 2300
Temp 73
Voltage 32.7 (initially 24.7)
Current 0 (initially 4.28)
Desired output 56p
Instant Salinity 0
Product name AL-1
Software revision r 1.55
Cell type t-15
 

Attachments

  • image.jpg
    image.jpg
    388.3 KB · Views: 2
  • image.jpg
    image.jpg
    388.7 KB · Views: 2
Based on the voltage drop, the current should be reading higher.

It might be low salt, a bad ammeter on the board, a bad transformer, bad rectifiers, or maybe bad relays on the board or other bad board components.

I would triple check the salinity first.

Can you show pictures of the transformer, rectifiers, and the front and back of the main board?
 
Last edited:

Enjoying this content?

Support TFP with a donation.

Give Support
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.