SWG not properly detecting salt level

PoolInMN

Member
Oct 6, 2018
21
Minneapolis
I have a Hayward Aqua Rite salt water generator that doesn't seem to detect the salt level correctly. I have a salt level in the pool at ~3300 PPM after adding salt earlier this year and testing the level with test strips. Whenever the SWG starts up though it gets a reading closer to 2200 PPM and so doesn't generate chlorine. When I manually set the salt level it does start generating but then after the pump is off for 12 hours or so and starts back up again the detected salt level drops back to 2200.

Has anyone else seen this type of issue? The control unit seems to be working fine and I have a brand new salt cell that I just purchased hoping that it would fix this.

Is it possible to tell the unit to generate chlorine regardless of the salt level that it detects since I know the salt level is high enough?


Thanks.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
22,404
Laughlin, NV
Can you tell us what brand/model SWCG you have? Can you add that information, along with more detail, into your signature?
 

JamesW

TFP Expert
Mar 2, 2011
16,525
What are the diagnostic readings?

Press the little black button and note all readings. Then, move the switch to off for a minute and then back on and recheck all diagnostic readings.
 

PoolInMN

Member
Oct 6, 2018
21
Minneapolis
What are the diagnostic readings?

What cell did you get?
Pool Temperature - 74
Voltage - 25.2
Amps - 4.48
Desired Output - 100
Instant Salt Level - -3800 (This reads 0 after the pump is off for 12 hours and started up again)
Program Code - AL-0
Version - 1.58
Cell - E-9

I purchased Amazon.com: Blueworks BLT9 Cell | T-Cell-9 Compatible with Hayward Goldline AquaRite Systems | Cell Plates Made by USA Company | 5 Year Limited Warranty (White): Garden & Outdoor though I had very similar problems with the OEM cell that I was replacing.
 

JamesW

TFP Expert
Mar 2, 2011
16,525
Ok, you have a generic T-9 and not a Hayward T-15.

The instant salinity looks right, which means that it's working correctly.

You can update the instant salinity by going to the instant salinity and moving the switch from auto to superchlorinate and back to auto.

Does the box remain powered when the pump is off?

When the pump turns off, the flow switch should turn off production and the power should be removed from the box.

Note that the cycle time is 180 minutes. The production is determined by the percentage setting. For example, at 50%, the cell is generating for 90 minutes and then off for 90 minutes. During the off part of the cycle, the amps and instant salinity will be zero. The "Generating" light will be on any time that the switch is in the auto position even when the cell is in the off part of the cycle.
 

PoolInMN

Member
Oct 6, 2018
21
Minneapolis
Ok, you have a generic T-9 and not a Hayward T-15.

The instant salinity looks right, which means that it's working correctly.

You can update the instant salinity by going to the instant salinity and moving the switch from auto to superchlorinate and back to auto.

Does the box remain powered when the pump is off?

When the pump turns off, the flow switch should turn off production and the power should be removed from the box.
Yep, the instant salinity is right now after I manually set the salt water level following the process that you outlined. The problem is though that if I turn the pump off for 12 hours and then turn it back on that instant salt level will read 0 until I manually set the salt level again.

The box does remain powered on when the pump is off. Are you saying that it should shut off completely when the pump goes off?
 

JamesW

TFP Expert
Mar 2, 2011
16,525
If the cell is generating with no flow, it can build up chlorine and hydrogen gas and explode.

When the pump turns off, does the box say no flow?
 

PoolInMN

Member
Oct 6, 2018
21
Minneapolis
If the cell is generating with no flow, it can build up chlorine and hydrogen gas and explode.

When the pump turns off, does the box say no flow?
I just played around with this a bit and it looks like it isn't correctly switching on "No Flow" when the pump stops. If I wiggle the wire that goes to the flow detector then it does flip to "No Flow" and then when I turn the pump back on it correct detects there is flow again and the light turns off. Consistently though I have to wiggle the wire to get it to detect the "No Flow" condition.

I assume this means there is something up with the flow detection? Any tips?
 

JamesW

TFP Expert
Mar 2, 2011
16,525
Due to the risk of explosion, it's important to have dual safety interlocks.

One interlock is the flow switch and the other is removing the power when the pump is off.

You have been operating with only one interlock, the flow switch, which has worked up until now.

Right now you should replace the flow switch and install a timer that can turn the box off during the scheduled off time for the pump.

Any time that the pump is off, the power to the SWG box needs to be shut off.

Until the fixes can be done, the switch should be kept in the off position.
 

PoolInMN

Member
Oct 6, 2018
21
Minneapolis
Due to the risk of explosion, it's important to have dual safety interlocks.

One interlock is the flow switch and the other is removing the power when the pump is off.

You have been operating with only one interlock, the flow switch, which has worked up until now.

Right now you should replace the flow switch and install a timer that can turn the box off during the scheduled off time for the pump.

Any time that the pump is off, the power to the SWG box needs to be shut off.

Until the fixes can be done, the switch should be kept in the off position.
Awesome, this is extremely helpful. I'll let you know how it goes.
 
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JamesW

TFP Expert
Mar 2, 2011
16,525
Here's an example of what can happen if the cell explodes.

 

PoolInMN

Member
Oct 6, 2018
21
Minneapolis
Here's an example of what can happen if the cell explodes.

Crazy. I guess I've just been lucky then since we bought this house 2 years ago and I think the SWG has had this problem the whole time. I honestly hadn't even realized that there was a separate flow detector, I had been assuming that was part of the salt cell functionality to detect flow.

In any case, I'm curious how people normally setup the hard off when the pump goes off?