ECC Forum

I needed a probe in my cooler mash tun, and created this probe housing that others might find useful as well. I didn't really want to drill a hole into the side of the cooler when I could drill a hole in the top instead. Not only does this probe work great for taking grain bed temp measurements, but I plan to use it with a stopper in a fermentation carboy as well.

The build was extremely simple, 2 parts. Length of 3/8 OD soft copper, and a brass 1/4 to 3/8 compression union, Watts A-109. Doesn't get any easier than that

A few things that I ran into.. The tip of the probe wasn't exactly round, probably from melting it shut at the manufacturer, but I rubbed it on a piece of sandpaper and it cleaned right up and the union slid over. Also, I wasn't sure if the clear plastic that joins the probe to the wire would fit inside the copper. But with a little pressure it squeezed in. So I didn't have to make any permanent changes to the probe, other than sanding down the end, which I consider an improvement.

Its fully waterproof, and has already proven to be so handy that I'm going to make a second. And if your worried about brass, you can easily substitute stainless tubing/union.

Very nice. Did you have to cut off the clear plastic sheath from the top of the probe?

Nope. It was a tight fit, but eventually jammed in there.

Almost forgot. I did have to drill out the union with 1/4" drill bit so the probe would pass all the way through. But that was trivial.

I ended up having to cut the sheathing a bit on the probe side to get the compression nut up high enough. I didn't need to drill anything out though. I went with one for the mash and one for the HLT, and I'm planning to do a smaller version for the grant. With the soft copper I was able to bend it to shape to hang over the side of the keggle. I also plan to do something similar with the float switches recommended on another topic.

Thanks for the ideas and the controller. I'm doing my first temp controlled ferment in a fridge with 10 gallons. It is sweet to be able to log in to the unit in the garage and see that it's been keeping my temperatures tight. This is really taking my brewing up another notch.

Shake

This is a damn smart design. Thanks.

Just stumbled on to this. Perfect for what I want to do. So thanks for posting it. One question: how is the compression fitting attached to the copper tube?

Thanks!

This was a very old post. Since that time, http://www.brewershardware.com/ has offered off the shelf probes of various lengths as well as thermowells to just drop your existing probe into.

JonW wrote:This was a very old post. Since that time, http://www.brewershardware.com/ has offered off the shelf probes of various lengths as well as thermowells to just drop your existing probe into.

The point was to use my existing probes. I was trying to avoid a thermowell. I wanted my probe in direct contact with the wort.

I would be concerned with all the little places that bacteria could hide in the extension fitting. A thermowell wouldn't be much more than the cost of the coupler and tubing components and would be much easier to clean and feel confident that it's not going to infect your wort.