Hayward swimpure not working

[sonoman]

I have a Hayward swimpure that is probably 4-5 years old. The past couple weeks the salt indicator has been falling, which made no sense so I had it tested and it is 3100 ppm. Display says 2100 ppm. Low salt and check cell lights are lit, and generating light is dark. Pool chlorine level tests near zero.

I cleaned salt cell with acid wash and took it to be tested. It passed. But I still have the low salt and check cell lights lit. What's going on? The guy at the pool shop (Leslies) is trying to tell me the swimpure control box is bad, but I don't believe him.

Other info. The whole system is controlled by a Pentair suntouch. Pool is 27k gal

 

[JamesW]

Is the "Power" light on?

 

[duraleigh]

Pool chlorine level tests near zero.

I can't help with the fix but you need to manually introduce some chlorine very quickly.

 

[sonoman]

Yes the light is on

And I added chlorine the old-school way

 

[JamesW]

Can you scroll through the diagnostics and post the readings?

As the cell gets older, it begins to read the salt level as lower than it is.

 

[sonoman]

Today, it looks a little better. It still says "check cell". I can clear it today. It also says, "check salt" and reads 2600 after I cycled the power.

Readings:
Temp: 74
Cell volt: 26.5 (a little high)
Cell current: 4.44 (a little low)
Desired output: 76%
Instant salinity: 2600
Product: Al-0
Release: 1.40

there is also a reading of -2100. I don't know what this refers to

 

[JamesW]

When the salt reading has a - in front, that is the instant reading. Without the -, it's the average reading. I think that you're probably OK. The cell is probably reading a little bit lower than the actual reading. I would have the salt double-checked to make sure of the reading.

If the salt reading is between 2400 and 2700, the box will give a "check salt" light, but it will still work. If the salt reading is below 2400, then the box will not work.

If the cell is reading lower than actual, you can make it work by adding enough salt to get a reading above 2400 ppm. You can keep adding salt as the cell fails to keep it working, but I usually stop when the cell is reading 1,000 to 1,600 ppm too low.

One of the best salt test kits is the K-1766. It would probably be worthwhile for you to get one of those.
http://tftestkits.net/K-1766-Taylor-Salt-Test-p31.html

You can tell the age of the cell by reading the first 4 characters of the serial number on the cell. The first character is the number of years of the warranty. The second character is a letter, which identifies the piece of equipment; the cell uses an "E". The next two characters are the year of manufacturer. For example, a 3E09 has a 3 year warranty and was made in 2009.

If "Inspect Cell" is blinking, it might be a timed reminder to check the cell for scale. You can usually clear this by holding the "Diagnostics" button for 5 seconds.