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Apex temp probe calibration


Delphinus88

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Has anyone calibrated their temp probe?    This time of year I struggle keeping the tank as stable as I would like.   It's cold in the morning and warmer during the day.    So if the heat for the house is on in the morning, the house may get a little too warm by the afternoon.    So I'm looking at my apex and wondering just how accurate the temp is.  I would assume the fluctuation I may see would tell me the degree of change but I really want to know what the actual temp is.    Before I go buying a NIST calibrated thermometer I was wondering if anyone here has one I could borrow for about 5 minutes. 

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I don't. I aim for temperature stability, not necessarily accuracy. I do keep an old-fashioned glass laboratory thermometer (traceable to NIST standards) around should I need check how far off the reading is from "truth."

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  • 3 years later...

My Apex thought the tank was running hot...when I tested against a thermometer the Apex was off by +8 degrees.  I opted to re-calibrate probe and see if that resolves the discrepancy.  Has anyone else ever had to re-calibrate a temp probe or should I err on side of caution and replace?  

 

Had a few power outages recently, but uncertain in that is when the discrepancy started...anyone know of any known causes of temp probe wandering?

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I would recalibrate it and see depending on what types of redundancies you have in place if it is not going to have any accuracy.   I never did get a high accuracy temp probe (NIST) but used everything I had to measure water temp and averaged those.  Most were really close.   Makes me wonder if recalibration is needed as part of regular maintenance?  

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15 hours ago, John said:

My Apex thought the tank was running hot...when I tested against a thermometer the Apex was off by +8 degrees.  I opted to re-calibrate probe and see if that resolves the discrepancy.  Has anyone else ever had to re-calibrate a temp probe or should I err on side of caution and replace?  

 

Had a few power outages recently, but uncertain in that is when the discrepancy started...anyone know of any known causes of temp probe wandering?

 

Early on, I used to check my Apex sensor against my NIST-traceable glass thermometer (see post from earlier in the thread above). However, I've not done this in a very long time. Your post is a good reminder that we should check these things from time to time.

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On 1/20/2020 at 7:07 PM, John said:

My Apex thought the tank was running hot...when I tested against a thermometer the Apex was off by +8 degrees.  I opted to re-calibrate probe and see if that resolves the discrepancy.  Has anyone else ever had to re-calibrate a temp probe or should I err on side of caution and replace?  

 

Had a few power outages recently, but uncertain in that is when the discrepancy started...anyone know of any known causes of temp probe wandering?

The probe that came with an Apex Lite I got from another WAMAS member had to be recalibrated from time to time (~6 months). I first noticed that the difference in the reading between the Apex and the digital display in the Finnex heater changed over time (there was always a discrepancy to start with), so I started checking the temperature in the system with another thermometer (NIST) on maintenance day. It was surprising to find the reading drifting upwards and by doing so, driving the real temperature of the system down by a degree or two in the span of a few months.

Since then I have switched to the new Apex and haven't noted any temperature drifts....yet

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Opened case with Neptune, they said to replace probe...only 4 years new...oh well...

Thanks for the discussion / feedback.


Sent from my iPhone using Tapatalk

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