10 replies to this topic

[gnef]

I am looking to use a 1/2'' NPT x 1/4" compression fitting to put a digital temperature probe in the way of the wort as it goes through a two stage counterflow chiller that I built. I don't want to use the double ferrule that comes with the fitting, but I am having a hard time finding the dash number for the o-ring size. brewers hardware sells the o-ring, but they give no specifications, and I assume it would be in poor taste to ask them, just to purchase them somewhere else.

 

Any ideas on the dash number? Here is a link to the o-ring I would like to get: https://www.brewersh...ng-for-1-4.html

 

At least, I believe the is the o-ring I would need. I put a micrometer to the temperature probe and measured .15 inches. I need an o-ring that can seal that against the fitting (I just ordered the fitting online, so I don't know what the OD of the O-ring should be).

[3rd party JKor]

Weird, i was just wondering the same thing. Let me know what you find out. It looks to me like brewhardware.com has a different o-ring to fit the 1/4" comp fittings.

[gnef]

Yea, I would order from him if his prices were more reasonable. I found a stainless 316 fitting for just under $7 shipped on ebay, and his setup is $14, and I don't know what he charges for shipping. I figured if I can source the o-ring cheaply, then I've saved some money on this little side project.

 

I've got an o-ring kit for buna-n o-rings, which I believe would be fine material-wise, but the profiles for the smaller o-rings are really thin, and this looks like it needs a thicker profile o-ring than what I would have on hand.

 

I've tried searching online, but the best I could find was a hbt thread that never resolved. What I may have to do is wait till I receive the fitting, and then measure the cavity dimensions where the o-rings would sit, and find the nearest dash number that will work, and just order it, or find it at Ace Hardware.

[HVB]

Not much help with size but I did this by making my own o-ring out of some scrap silicone tubing.  So far so good.

[gnef]

That is an interesting thought. When the fitting comes in, I'll take a look at what I can do.

 

I was just browsing the sizing charts, and it looks like the only size that could work in my mind is a -105 sizex 5/32x11/32. I just don't know if that would be thick or wide enough to seal properly from where I would be removing the ferrules from.

[gnef]

well, I went ahead and ordered the -105 o-rings from amazon. They only sell in packs of 100! So if they work for this, you are welcome to have some JKor.

[3rd party JKor]

well, I went ahead and ordered the -105 o-rings from amazon. They only sell in packs of 100! So if they work for this, you are welcome to have some JKor.

 

 

[gnef]

Everything arrived today. I just did a quick check for fitment, and these -105 silicone o-rings seem to be just right, and can double stack in that space for the double ferrule. JKor, if you pm me your address, I'll send a small handful to you. How many fittings did you need this for?

[gnef]

here is a quick photo I took:

[gnef]

Here is a quick photo of the finished product: 

 

This is a two stage counterflow chiller I built about 3 years ago. I only used it a couple times, and found it more tedious to use, but part of that was trying to measure the outlet temperature by sticking the probe into the outgoing stream into the bucket. I want to try using this thing again, but to make things simpler, I needed to get this fitting so that I could place the temp probe in the outlet without having to constantly fiddle with it. 

 

I haven't checked for leaks yet, but I tightened everything down and used teflon for the threads, and added keg lube to the o-rings, so it may just be the next time I brew is the test. haha. 

[gnef]

Just as a final confirmation, these are definitely the right size to use for this purpose!

 

I replaced the unused sight gauge on my HLT with one of these fittings, and with the temperature probe in it with the two o-rings, it did not leak at all, and when I used the chiller, it was sealed well also. In fact, the chiller worked better than I expected, and I was able to monitor the temperature as I chilled nicely, not having to worry about placement of the probe.

 

I'm glad I gave it a try, the setup I have now is much better!