A419 probe waterproof?

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quigsnshad

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I just wired the Johnson A419 temp. controller and the probe doesn't look too watertight. Any problems if I silicone the wired end where the crimp is? Plan on placing this in a glass or a gel pack and don't wanna ruin it.
 
Rather than waterproofing it and placing it "wet" for a buffer. I think a similar buffer can be achieved by insulating it dry w/ paper towels or bubble wrap. I think I just read of someone using dryer lint to pack the probe inside of a glass vial. I just wrap the probe w/ paper towel and tape some plastic wrap over it to keep it from getting damp.
 
I insulate my probe with foam insulation (the pink foamboard stuff) and I think I'm going to have to replace my probe. It's now 2-3 degrees off from other thermometers. I was thinking about putting some silicone sealant around the new one.
 
I just wired the Johnson A419 temp. controller and the probe doesn't look too watertight. Any problems if I silicone the wired end where the crimp is? Plan on placing this in a glass or a gel pack and don't wanna ruin it.

That should work or you could put a piece of silicone tubing over it. Watertight heat shrink tape is another option.
 
Thanks for the heads up regarding the silicone. Thinking of using an old vial now and drilling a hole through the cap and sliding an o-ring towards the wire end of the sensor so it doesn't end up taking a bath. Thanks everyone for your input.
 
I have the A419. Its hard to get a straight answer out of Johnson Controls about how waterproof the device is but as one poster said he was told it was "splash proof". That doesn't/didn't encourage me to let it soak in the beer, besides God knows what's in the plastic and will leach out, nor does it encourage me to soak it in a bottle of liquid or some such. I came up with an idea I used for my outdoor weather station which has several similar "probes". Take an appropriate diameter piece of tubing and plug the end with silicone gel. I plugged about an inch worth to be sure the plug stayed in. Then cut it to length you'll need to insure it stays a couple of inches above liquid level in whatever vessel you place it in. Mine I extended a couple of inches beyond the top of the jug so I can get hold of it easily. I use a gallon apple cider jug about half full of sanitizer. I then push the probe and its prophylactic down into the water such that the entire metal part of the probe is below the liquid level. As the freezer, my lager device, turns on and off the liquid in the cider jug assumes about the same temp as the beer. Only caveat is making sure the tubing is long enough to extend above the opening of the jug... And checking the water tightness of the plug in the end seems intelligent so I do that every time I move it. So far no leaks so...
 
I posted a message about creating a tube and closing the end off with silicone. That would be okay as the part that is sensitive is the jacket for the wire and not the metal tip. Likewise the wire is not exposed to the silicone plug while the silicone is wet. In fact, I waited a week or more to be sure the silicone was fully cured. AND, if still concerned a small wad of paper or cotton ball can be pushed down the tubing ahead of the metal sensor and keep the entire works away from the silicone. I didn't do that because silicone isn't reactive with aluminum... if it were, I'd have drowned in my sailboat a long time ago as many of the fittings were waterproofed with silicone LOL. But, protecting the plastic sheath of the probe from silicone is important as that is reactive. But, all it takes is letting the stuff in the end of my homemade tube completely cure and then placing a small wad of paper or cotton in it as a spacer.
 
Don't put silicone gel anywhere on the plastic sheathing of the probe. The plastic is reactive to the silicone... see my two other posts, GatorDad and the mounting/location warnings in the user manual for the device. They say don't allow it in contact with wet silicone... I assume that means uncured as I invented a little waterproof device that has a silicone plug in the end... a length of tubing like used to transfer wort and such... which hasn't damaged the probe. I took a length of tubing and plugged the end with silicone. Allowed it to fully cure. That needs to be done to insure it doesn't slide out or leak. Then put the probe down the the tube and insert the works into a jar of liquid near the beer...usually in the blow off jug. So far so good. The tube extends above the jar. BUT, I might add a wad of paper or cotton ball in the tubing to absolutely insure no part of the probe touches the silicone seal plug.... just in case. So far after four uses my little device works and hasn't damaged the cable or the metal probe. Above all one needs to protect the sheathing of the cable from silicone which I suspect while still "wet" can dissolve the sheathing and ruin the probe.
 
http://cgproducts.johnsoncontrols.com/MET_PDF/125186.PDF

Johnson claims the probe is "splashproof". I've been running mine (for quite a while) with it submersed in a small bottle of water and no issues. I think many others here are doing the same. YMMV.

BTW, stay away from silicon with this probe. See last item of "Mounting Considerations" in link above.

Yeah, mine had been submerged for ~5 years with no problems.

Wasn't aware that I probably shouldn't be doing that. :eek:
 
I submerge mine in the tub of water i put my fermenters in and have had no problems. Also have one running in my saltewater fish tank with no issues. I did shrink wrap the junction between the ss end and the wire just for ease of cleaning. i did tear one apart and the thremisor and wire connection itself is potted in an epoxy material so i think they are pretty watertight. I built a ss thermowell for use when i am directly sensing beer temps as I wasn't about to submerge the probe directly in the fermenter.
 
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