temp probe out of control on AC jr!!!! PLEASE help!!!

[jennmac415]

I recently purchased a used AC Jr and I finally got to programing it tonight with the help of a friend...

All was well for a couple of hours and all of a sudden the temp was jumping up to 90 on the Ac unit using the temp probe!!!!!!!!!... BUT all of the other 3 thermometers on my tank were showing the temp to be around 79.5.....I read about calibrating the temp probe, but if I calibrate it according to the 3 thermometers all showing 79.5...I will have to calibrate the probe over 10 degrees down!!!!! What is going on??? Is the probe bad??? What should I do???

[jennmac415]

Ok, I just chcecked on the tnak again and the temp on the Ac Jr unit is reading 94!!!!! BUT all three of the other thermometers are showing about 78.9...WHAT is going on??? What should I do? I am worried if I leave the heater online with the AC Jr and the probe keeps reading too high the heater will not actually come on all night and the tank will actually be too cold...should I just take it off the unit until I can get a new probe???? :(

[addicted2reefin]

take it off for now, and then try to calibrate the probe.

[jennmac415]

I did calibrate the probe and in order to make it match the temp of the other 3 thermometers it has to be decreased almost 10 degrees...is this normal or do I have a bad temp probe?

[PowermanKW]

I had to calibrate mine, but only a degree. 10 is way off. Something is wrong. What are your other probes. Are they reliable.

Not real crazy for things to be off a degree or two. Measure against a real thermometer.

[tylorarm]

I quit using my AC because of the temp probes. I had a couple go bad, both times was a big PITA because it wasn't just a degree or so off, more like the 10 degrees like yours. It seems to be the weak link of the AC systems.

[jennmac415]

great...did you ever contact the company to see what they said???

[tinnghe]

Contact Neptune they will work with you if yours still under warranty then it will be replace by them

[jennmac415]

I don't think it will be under warrenty as I bought it from a RC member...:(

[tylorarm]

I had one replaced by warranty, one outside of warranty. Both times service was good, but after the damage was done. Nothing like having your chiller on when the AC controller read 85 degrees and the tank's true temp is at 72 degrees, that's the sort of thing i came home to...After that, i used the AC temp for internet update only, used ranco to control heaters and chiller. Then got tired of bad reads making me nervous, dropped the AC altogether. Ranco has been flawless 9 years now, and i have 3 of them.

[jennmac415]

ok... put the AC temp probe and my other tamp probe in a cup of water...AC Jr probe running about 8-9 degrees warmer than the other probe...