Temperature Reading Fluctuating Significantly

[ponokareefer]

I took down my system, moved it and set it up temporarily until my new system arrives. My Apex Jr. controller was working great prior to the tear down. After I set up my system temporarily, the temperature readout from the probe is all over the place. It varies from 27.2F to 55F, and jumps up and down constantly. The tank temperature is actually at 77.2F. Can anyone help me get this resolved? I didn't bump/drop/get water in the system, so what is going on? I tested the probe in different waters and it is doing the same thing no matter what it is in. I cleaned it off, but it was already really clean.

[aquamanic]

Double check that your temp probe is still set to read in F and not C. It's on the probe/input web page (not available in Fusion).

[kenargo]

It sounds to me like you are set to read in Celsius (27.2 == 80.96) but since the temp is jumping to 55 that sounds like the temperature probe is going bad (or about to go bad).

[ponokareefer]

I had confirmed that it was set in C. I just bought the entire system 2 months ago.

[ponokareefer]

Sorry, meant F not C. I'm guessing it must be a bad probe.

[aquamanic]

Those would be strange readings then - typically if a temp probe fails it does so quickly and will read either 20 or 120 depending on whether it shorts open or closed.

[ponokareefer]

It seems to have returned to normal this morning. Do I trust it?

[kurt_n]

Could it have been from some type of electrical interference?

Just picturing that in a temporary installation, the cables might not have been routed the cleanest. And they probably were routed different than before. Did you move the cables around just before the reading returned to normal?

[ponokareefer]

I left the unit connected overnight and in the morning, it was working normal.

[aquamanic]

Temp probes are not known to be influenced by EMI. Not saying it can't happen but it's not something I've heard about.

All you can do is watch yours for a while. I'd make sure I had some safety code in my heater and chiller programs though to protect me if the probe reads well outside what the likely tank temp is so you don't boil or freeze your tank. That's a best practice anyway.