Which one should I believe?

[Satori]

Ok, so I just got my new Neptune Jr controller. The problem is, it shows a different temp and pH than what I had before.

The controller says 79.3 degrees, my "Little Time & Temp" says 80.6.

The controller says 8.14 pH, my pinpoint pH monitor says 8.00. I calibrated both just now using 7 and 10 fluid, and they still read differently.

Which one is right? I tend to believe the controller, but I guess I'm biasing that on which one cost more. Is that wrong?

 

[NaClH20NMYVEIN]

I hated my Little temp and time meter, I had 2 and both were off by 4 degrees. I would trust my finger more than one of those.

 

[Satori]

Are the mercury type thermometers accurate? I guess the question would be, how would I know what is accurate?

 

[clkwrk]

Are you using electronic ballasts?

 

[Satori]

Icecap electronic ballasts, but I'm not controlling anything yet; just monitoring temp and pH. The x-10 isn't connected.

 

[Satori]

clkwrk, are you suggesting EM interference from the ballasts?
The ballasts are mounted to the back of the canopy and the controller is inside the door of the sump, a good 3 feet away including 18 inches of water.

 

[clkwrk]

Yes I am suggesting interference.

Even at a whole 3 ft This is a very common problem with the AC's.

Best way to check is to shut of the ballasts 1 by 1 while watching the screen and see if the temp changes.

Btw my icecaps make my electronic door bell ring for no reason also .

 

[Satori]

<a href=showthread.php?s=&postid=6896477#post6896477 target=_blank>Originally posted</a> by clkwrk

Btw my icecaps make my electronic door bell ring for no reason also .

That's funny!

Thanks for the suggestion, I just turned all four ballasts off one by one, waiting about 15 seconds in between each one.
The temp on the controller never moved though.

 

[clkwrk]

Then you are lucky and I would trust the AC unit .Especially if both the unit and probe shipped together. If so they usally are calibrated wit each other.

 

[Satori]

It came new with temp and pH probe today.
Thanks, I was leaning toward trusting the AC unit.

Now, how about the difference with the Pinpoint pH monitor?

 

[clkwrk]

I would believe the controller again . I have 2 milwaukee sm122 ph controllers and both match my 2 aquacontrollers and both aquacontrollers match each other.

 

[North Bay 101]

MSM,
You can check the accuracy of any temp probe by checking against a known. Take a styrofoam cup and fill it half full of ice and add water. The water will get to 32.0 degrees it will take a minute or so. This will be your known. Can you adjust the temperature in the AQjr?

 

[Satori]

Awesome.
Thanks for the real-world comparisons.
My Pinpoint is going on 2 years old, so maybe the probe is getting old.

 

[Freed]

How do you know that what you are calibrating something with is actually calibrated correctly?

 

[Satori]

Norh Bay,
I'll try that just for kicks. Yes, I can adjust the AC temp.

 

[Satori]

Freed, if you mean pH, I have a bunch of single-use pH calibration fluid packets. I have 4.0, 7.0, and 10.0.

 

[clkwrk]

<a href=showthread.php?s=&postid=6896650#post6896650 target=_blank>Originally posted</a> by Freed
How do you know that what you are calibrating something with is actually calibrated correctly?

Ph 7 and 10 were used for ph calibration as mentioned above. I don't get what your saying?Are you talking temp ?

 

[Freed]

How do you know your pH 7 solution is actually a pH of 7 and not 7.5 or 5.3 and your pH solution of 10 is actually 10 and not 9.1 or 12.6?

 

[Satori]

It's "certified by NIST" standards. Each packet is sealed and intended for single use.

 

[clkwrk]

Because Randy has tested them