Inline temp probe method

[thuperman]

I've bought a DS18B20 temp probe like the following:



I'm trying to fit it inline near the outlet from my Crown urn using a tee-piece.






One method I found was to buy a 1/2" MNPT x 1/4" compression fitting, but they are so hard to find.


Brewhardware.com in the States sell one, but the lack of local options has me thinking that others are using another method.

Anyone got a simple method for placing the DS18B20 temp probe inline in the plumbing?

Much appreciated!
:beer:

 

[klangers]

You need a thermowell. Screw this into the T piece and then put the probe into the thermowell with some heat sink paste.

 

[Adr_0]

Those threaded/tube fittings need to be drilled out - so wouldn't work anyway.

You could also use a gland, eg from au.element14.com. Polyamide/PA6 is rated for long term use at 100°C. But the rubber rings probably aren't.

Might be hard to get a 1/2" BSPP/G, but you could potentially put a hole in your kettle or push in a nylon gland (with a spanner) and you should get a good seal.

EDIT: you're probably best off with a short thermowell, paste, and a nylon gland keeping the cable/probe firmly in place.

 

[klangers]

I am very skeptical as to the suitability of a cable gland to seal liquids under pressure.

A thermowell is designed for exactly this application.

 

[Adr_0]

I am very skeptical as to the suitability of a cable gland to seal liquids under pressure.

A thermowell is designed for exactly this application.

Yep you're right - thermowell + paste + gland is the way to go. Sorry, I was probably doing and explaining too many things at once. A nylon 1/2" npt gland should be able to be wound up into a 1/2" thermowell female thread on the back of the thermowell.

 

[Robbo2234]

You can get submersible cable glands google THOMAS & BETTS 2672 these would be too big but will start you in the right direction also search for hazardous Glands I think you should be able to get a stainless steel gland

 

[thuperman]

Please pardon my ignorance, but I thought the stainless steel encapsulation shown in the first picture is essentially a thermowell. It's advertised as "waterproof" and is rated from -55°C to +125°C. I assume that the only reason to put it inside another thermowell is because this one has no threading to attach it to the tee-piece. Have I got this right?

I should also add that the temp probe cost me $2.53 on eBay and I haven't purchased the tee-piece yet, so I'd happily replace it with a simpler solution. I'd rather avoid having to drill another hole into the urn for the temp probe (keep it inline in the plumbing), if possible.

 

[klangers]

Please pardon my ignorance, but I thought the stainless steel encapsulation shown in the first picture is essentially a thermowell. It's advertised as "waterproof" and is rated from -55°C to +125°C. I assume that the only reason to put it inside another thermowell is because this one has no threading to attach it to the tee-piece. Have I got this right?

I should also add that the temp probe cost me $2.53 on eBay and I haven't purchased the tee-piece yet, so I'd happily replace it with a simpler solution. I'd rather avoid having to drill another hole into the urn for the temp probe (keep it inline in the plumbing), if possible.

Nah that's just the body of the probe which covers the highly sensitive RTD element. Even industrial probes are put in thermowells:

A thermowell has threads so it can actually be part of a pressure-rated pipework system, and you can remove the probe without opening any part of the pipework.

 

[damoninja]

I know it's not what you're looking for, but I just went through the side of my crown, quick point punch and step bit and was done in a few minutes.

 

[thuperman]

OK, so if I've got this right, I could use a thermowell like this (1/2" internal thread x 1/2" external thread). Fill it with heat sink paste and put the temp probe in. Seal it with epoxy glue. Then use a waterproof SS cable gland like this (1/2" thread) to keep the probe inside the thermowell.


Questions:
1) Have I got the idea above right?
2) Does anyone know what length thermowell works best for a tee piece like this?
3) Do I need to use epoxy glue if I am using the gland?
4) Is there anything else that I've missed?
5) If this is a common way for people to install their temp probes (in a tee-piece), why do so few HBS's stock the required parts?

 

[GrumpyPaul]

https://m.aliexpress.com/s/item/32695268070.html?trace=wwwdetail2mobilesitedetail&productId=32695268070&productSubject=USA020-Thermowell-Immersion-Sleeve-Pocket-Stainless-Steel-304-BSP-1-2-for-Max-6mm-OD-Wire&spm=2114.01010208.3.1.1CF9UJ&ws_ab_test=searchweb0_0,searchweb201602_2_10152_10065_10151_10130_10068_436_10136_10137_10157_10060_10138_10131_10155_10062_10132_10156_10133_10154_10056_10055_10054_10059_10099_10103_10102_10096_10147_10052_10053_10050_10107_10142_10051_10084_10083_10080_10082_10081_10110_10175_10111_10112_10113_10114_10181_10183_10182_10185_10078_10079_10073_10070_10123,searchweb201603_9,ppcSwitch_5&btsid=93856ae8-c40a-40d8-850b-d283f02f159c&algo_expid=fa2fbf1a-4d60-41d2-a211-300c617f0320-0&algo_pvid=fa2fbf1a-4d60-41d2-a211-300c617f0320#autostay

This maybe?

 

[fdsaasdf]

OK, so if I've got this right, I could use a thermowell like this (1/2" internal thread x 1/2" external thread). Fill it with heat sink paste and put the temp probe in. Seal it with epoxy glue. Then use a waterproof SS cable gland like this (1/2" thread) to keep the probe inside the thermowell.


Questions:
1) Have I got the idea above right?
2) Does anyone know what length thermowell works best for a tee piece like this?
3) Do I need to use epoxy glue if I am using the gland?
4) Is there anything else that I've missed?
5) If this is a common way for people to install their temp probes (in a tee-piece), why do so few HBS's stock the required parts?

I'm not an expert but do have thermowells in my system - firstly you don't want that thermowell as it's 201 stainless. Aim for 304 (or 306 but usually more expensive)

1) Generally yes. Look around for threads on installing thermowells, there are many
2) You'll probably not be able to find one that fits off the middle opening of that fitting. I run my 2" thermowells at one end of the tee so the liquid is effectively travelling through an elbow.
3) No
4) Possibly...but it looks ok to me
5) Keg king sell the bits, barring cable glands. Craftbrewer probably do too. I got all of my SS fittings and probes from China due to price. I would suggest that the market for these DIY builds isn't huge yet, or at least the HBSs haven't had many enquiries. You could try calling one to discuss?

 

[huez]

or this local

https://onlinebrewingsupplies.com/hardware-plumbing/thermo-wells/herm-it-174-thermo-well-kit

 

[fdsaasdf]

https://m.aliexpress.com/s/item/32695268070.html?trace=wwwdetail2mobilesitedetail&productId=32695268070&productSubject=USA020-Thermowell-Immersion-Sleeve-Pocket-Stainless-Steel-304-BSP-1-2-for-Max-6mm-OD-Wire&spm=2114.01010208.3.1.1CF9UJ&ws_ab_test=searchweb0_0,searchweb201602_2_10152_10065_10151_10130_10068_436_10136_10137_10157_10060_10138_10131_10155_10062_10132_10156_10133_10154_10056_10055_10054_10059_10099_10103_10102_10096_10147_10052_10053_10050_10107_10142_10051_10084_10083_10080_10082_10081_10110_10175_10111_10112_10113_10114_10181_10183_10182_10185_10078_10079_10073_10070_10123,searchweb201603_9,ppcSwitch_5&btsid=93856ae8-c40a-40d8-850b-d283f02f159c&algo_expid=fa2fbf1a-4d60-41d2-a211-300c617f0320-0&algo_pvid=fa2fbf1a-4d60-41d2-a211-300c617f0320#autostay

This maybe?

Looks good

 

[thuperman]

Legends, all of you.

https://m.aliexpress.com/s/item/32695268070.html?trace=wwwdetail2mobilesitedetail&productId=32695268070&productSubject=USA020-Thermowell-Immersion-Sleeve-Pocket-Stainless-Steel-304-BSP-1-2-for-Max-6mm-OD-Wire&spm=2114.01010208.3.1.1CF9UJ&ws_ab_test=searchweb0_0,searchweb201602_2_10152_10065_10151_10130_10068_436_10136_10137_10157_10060_10138_10131_10155_10062_10132_10156_10133_10154_10056_10055_10054_10059_10099_10103_10102_10096_10147_10052_10053_10050_10107_10142_10051_10084_10083_10080_10082_10081_10110_10175_10111_10112_10113_10114_10181_10183_10182_10185_10078_10079_10073_10070_10123,searchweb201603_9,ppcSwitch_5&btsid=93856ae8-c40a-40d8-850b-d283f02f159c&algo_expid=fa2fbf1a-4d60-41d2-a211-300c617f0320-0&algo_pvid=fa2fbf1a-4d60-41d2-a211-300c617f0320#autostay

This maybe?

Looks great! Actually the max ID of this gland (USA020) is 6mm and the diameter of the probe is 6mm, so it could be too small, but the USB020 has a max ID of 8mm and would probably work better with some heat paste.

Has anyone used one of these and can confirm that a 15mm thread and 20mm probe is the right size to fit into the tee-piece so that the wort will flow past the sensor instead of at 90 degrees?

 

[GrumpyPaul]

Is that 8mm referring to the id of the thermowell out the gland around the wire?

I think it's the maximum thickness of the wire not the probe.

I can't see the internal dimensions of the but the probe goes in anywhere.

You might have to take one for the team and buy one to find out.

 

[thuperman]

The stainless tube in the temp probe is 50mm long, so the gland would have to go over that and not the cable itself. I presume that's OK?

 

[mxd]

https://www.dropbox.com/sh/pb62kkc019i40js/AACHX1L4Xo2Dk0GUyT0LmPV_a?dl=0

the above is mine, thats the return for my herms