Temp probe readings

Some history of my concern with my temp probe as I have been working with Vinny on R2R over the past two days, but i thought i would post here as well.

What is life expectancy of the temp probe? My temp probe says the tank is where it should be but the tank water felt a lot warmer then the set point. My temp probe is my original from years ago. Vinny responded with a couple of years, sometimes longer.

My analog probe was probably 10 years old, so it was due for a change anyway.

My next post after ordering a digital temp probe:

So i went ahead and had a digital temp probe dropped off this morning. I am not sure if its better then the analog, but since i have an expansion box 2, i thought i would try it. Is there anything else i need to do except plug it in? I had read that the digital probe is factory calibrated, but do i need to make sure the profilux knows its the digital probe? I see in my sensors settings that i have a temp 2, sensor index 9. I have no other temp cards except the P3 port and then the one in the expansion box 2. Is sensor index 9 the digital temp port? I checked in the system settings for the expansion box 2 and temp port is active. One reason i am asking about if i need to do anything else, is that i see under this sensor settings the same calibration data as the analog temp probe. Just want to make sure i am getting the correct reading. Again got a quick response from Vinny that only needed to plug it in.

This was my last post as of this morning:

I am concerned that the new temp probe is off as my tank water feels colder. My tank temp settings are 78 and the new probe is reading 82. My house is cooled and currently around 74. I have two cheaper digital probes that i checked against an ice bath and both came back at 32. Those probes are both reading 76 as is my adjusted GHL analog probe. I also have a 1 degree nocturnal change at night. The new digital probe hasnt moved from 82 degrees. I made sure to move it's wire away from any power cables and also adjusted the filter from strong to weak, with no change in its reading.

Based on the other probes it looks like my tank naturally wants to run around 76 degrees given how cool i keep the house and the few pumps that are running in the tank. Not sure which probes to trust, other then the feeling of the water being cooler. Hard to believe that the new probe could be 6 degrees off.

Why does the digital probe go up in temp reading when placed in ice bath?

Looking for others thoughts or suggestions. I realize my hand/fingers are not calibrated instruments so maybe the new probe is accurate, but if it is, and i have my heaters set to be controlled off of it, why didnt the tank temp drop over night? At night I run the house temp at 70 so would expect to see tank temp drop over the course of the night to at least the set point.

John

John,

The digital temp probe should also register a lower reading when placed in the ice water.
Is the probe stuck on 82° F?

Follow these steps to see if the temperature value of this probe reacts to the ice water:
1. Disconnect the probe from the port and disable this port (go to system page, select EXB2, click configure, disable temp probe, click OK)
2. Click Assign devices, uncheck the box for EXB2 to unassign, click OK.
4. Reconnect to P4, go to system page, re-assign the EXB2.
5. Reconnect to P4, go to system page, select EXB2, click configure, enable the port
6. Unassign EXB2 once again, re-connect, then re-assign EXB2.
7. Connect digital temp probe to the port.

Let the probe sit in ice water for a few minutes and see what values are shown.

I am traveling for a couple of days and will try this when I get home.

When I put the new probe in ice water it climbed in temp to 94.

Followed you steps above and it seems to have worked. I see where the ADC values have changed and the probe is now reading the same as the other probes. Originally the probe was reading 82 and now it’s 75. I haven’t performed the ice water test yet but will try that later to verify the probe is reading correctly throughout its range. Thanks for the help.