Solar heater won't turn off at preset temp...

[Magnew]

Hi everyone:

I've not had any problems with my GL-235 Goldline control system until now. I have my pool set at 90, and for years, once that is satisfied, the Goldline tells my pump to shut off, and it has without fail, until now.

For the past couple of days, it heats to 91 or even 92 and the pump keeps running (and the valve actuator is sending water to the panels). For grins, I dialed it down to 85 while it was running, and it shut off. But, it starts back up again after a while.

The whole system is so simple, I know, but I am scratching my head as to where to look. The sensors? I could do resistance checks but that seems to be a failproof part. The relay? Such a simple device. The actual board going bad on the GL-235 perhaps? I don't know how to diagnose that.

Any help would be appreciated!

Mike

 

[jblizzle]

I am guessing sensor. Check the wire and the connections for corrosion.

Posted with Tapatalk ... sorry if I sound short ... hate typing on phone

 

[Bama Rambler]

I agree with JB, it's possibly the sensor, but it could be a bad connection of the sensor wiring. The result would be the same.

 

[Magnew]

Water temp sensor, not the collector sensor, I presume?

 

[Bama Rambler]

Most likely the water temp sensor.

 

[Magnew]

Yep, I believe y'all are correct. I just measured the resistance of the water sensor, and the conversion says that there is about a five degree lower temperature than the actual temp of the pool water.

I'm surprised a sensor can go bad.

Thanks for the push!