Mash Temp Probe

[msjulian]

I am looking to add temp control to my HREMS setup. I am trying to decide where to read the temp from. I have a thermometer in the side of the tun about a third of the way up from the bottom now. I think I would want the temp controller probe to be reading the exit temp and then set the controller so that it keeps he temp in the middle of the grain the correct temp.

Does this sound correct? Any better ideas?

[Don]

Well, I'm a RIMS user and I measure the output temp at the Rims.
I also keep a probe in the middle of the tun.
I find that there is several degs difference in the two while I'm raising temps.
Once I get to the desired temperature my tun temperature will usually settle to within 1-1.5 degs of the RIMS output in several minutes.
When I'm hold the temp for 60 min my temps will stay within 1 deg of each other during the whole process.

I find by controlling the heat by the output temp (into the tun) this will keep me from overheating the mash and from cause other problems (scorched mash).

Again this is the process for RIMs, I think I remember when I was investigating the two systems that most people recommended to also control the HREMS by the output temp.
Your tun will catch up to the Herms output temp given some time.

One other factor I found plays an important factor is the flow rate. I keep my flow and @ 1/3 valve opening. That works for my system

[msjulian]

Thanks Don. I think from what I have found so far is what you eluded to. Most seem to be reading the tun output on the HERMS. Since the HERMS system does not have the wort in direct contact with the heat source there is not much chance of overheating. The system does not do step mashes as well as a RIMS but I don't do those very often. I am just looking to control the mash temps to +/- 1 deg. If I read the center of the grain bed and the output temp of the tun I think I should have a good handle on the overall temp.

[Don]

You will also (I think) have to shut down a little early so not to overheat.
You have a pretty big mass of hot water and it will hold a lot of heat.
The good part of that is once you reached the happy temperature you should be able to hold it there.
Let me know when you are brewing with it, i'd like to watch.

[msjulian]

I have run 5-6 batches through so far and I really like it. I have to control mash temp with the pump ball valve so I don't get recirculation during the complete mash period. I will recirculate till I see my mash temp come up to what I need and then shut the flow off. Most of the time if I have my HLT about 10 deg hotter then the mash temp I can keep the flow going for a good portion of the time.

This is a crude version of what I am going to build.

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This way I can set the temp to control the valves and let the system recirculate for the whole mash period.

Here are the solenoid valves and controller I bought.

Image[45].jpg

Image[44].jpg

As soon as I get it built I will post more pics.

[msjulian]

I think this is what I want to aim to build in the next 12 months...

IMG_0176.jpg

[jesskauffman]

Michael, I'd be interested in hearing what you think of the ECHOTech gas valve when you get it plumbed up. I've been eyeballing that same valve for doing a HERMS build similar to what you're thinking of building.

[msjulian]

Got the valves installed tonight. Now I am just waiting on my RTD probe to show up so I can test it out.

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