PH probe stopped working after only a month!

[kevinlo]

A nearly new ph probe stopped working and now reads a ph of around 7 in both of my controllers no matter what the actual ph of the solution is. This probe was running in a calcium reactor for about a month on a Milwaukee controller and of course I found my CO2 running non-stop. This probe was from Pinpoint. Another probe from pinpoint has been running fine in my sump for about a year. Both controllers are working OK.

 

Has anyone else had this happen? Could the CO2 in the reactor somehow cause a failure? The bulb tip looks physically fine. Do these things have warranties?

 

Sorta aggrivating at 1:00 in the morning.

[YBeNormal]

The reading on one of my probes dropped to 2.5 (or was it 4.5?) recently. I thought it was defective but I recalibrated and it is working fine now.

[scott711]

Have you tried to recalibrate it? I find that I have to recalibrate mine once a year.

[jwildman]

I would recalibrate. Also check the PH in the tank/sump and then put some tank water in a cup and test. Are they the same? If so, probably a probe problem. If not, I would add a grounding probe. I had this problem.

 

Also have you cleaned your probe? And yes it is very annoying

 

Regards,

 

John

 

 

Have you tried to recalibrate it? I find that I have to recalibrate mine once a year.

[kevinlo]

Somehow I always find issues in the wee hours of the morning

 

The probe reads 7 in tankwater with a ph of 8.2 and in effluent with a ph of 6.2. And in vinegar with a ph around 2.5. Re-calibrating doesn't work. If I recalibrate to the 4.0 fluid, the 7.0 fluid will then appear to be 4.0. This is confirmed on 2 controllers. The controllers are OK, because they work on another PH probe.

 

It seems strange that the probe would stop working so suddenly. I just wonder what caused it to fail. Is it that black cat that crossed my path at Home Depot the other day?

[kevinlo]

I spoke to Lou at American Marine Pinpoint and he figured out the problem. The glass inside the probe, under the plastic outer tube, was broken. Apparently I tightened the probe holder right to the threshold of breaking. It worked for a month, then in a recent temperature change, the plastic may have expanded just enough to break it.

 

So the moral is, don't overtighten those probe ports. Lou offered to replace it for free since it had only been a month. I don't think I'll take him up on it though since the issue was on my end. Anyways, lesson learned. Excellent customer service from American Marine!

 

Kevin

Edited April 16, 2008 by kevinlo