Ranco Temp Controller

[mrtian97]

I used 3 different temp gauge, the RkL, and 2 cheap temp gauge, all reading 79-80 while the Ranco is 86 and through time increased to 100. I know my tank doesn't have temp this high, room temp is maintained at 80 with AC and this was taken in the morning and at night (I am in Southern California so morning and night is pretty cool).
I think the temp sensor is bad, not sure why ETC Supply said they are fine.

 

[Lionfish Lair]

Same thing happened to me with my Reefkeeper elite. Had issues, I sent it off, they found nothing, but it's still not right despite what they said and I don't feel comfortable using it or selling it.

 

[CC13]

Same thing happened to me with my Reefkeeper elite. Had issues, I sent it off, they found nothing, but it's still not right despite what they said and I don't feel comfortable using it or selling it.

Do the Ranco's have to be calibrated at all?

 

[charleydavis]

well, I sent in my Ranco to ETC supply (where I bought it), 1 month later, they said nothing wrong with the sensor or the controller and sent it back to me.
I tested last night and the controller still showing high temp than the actual. My tank temp is about 79-80, and the Ranco showing 100 after leaving it overnight. I unplugged it this morning and plug it back, now showing 86. Again, it was working for 2 months or so. it has the pvc thermalwell installed by ETC supply to make it water proof. any suggestion?
I already moved on to RKL controller but would like to sell this unit since it's practically new, but don't want to sell defective unit
Thanks

Sorry to hear this. It appears that ETC Supply is useless. I will make a note to avoid buying from them.

FWIW - The most accurate "gold standard" for temperature measurement would be a mercury in glass lab thermometer. Of course, this not a controller. It is just a measurement, but a higly accurate and reliable measurement. Accurate to 0.1 degree F. It will never fail, unless the glass breaks. They are a bit expensive. Around $50 from Gilson Co.