Mash Temp for RIMS system

[burdbrew]

I utilize RIMS and am a big fan. I have a coleman extreme cooler as a mash tun (all though I debate switching to stainless all the time, but that's another thread). I have the temperature probe pretty close to where wort re-enters the mash. But I'm left wondering, if my RIMS is set to 154, is my mash 154? I put a hand held in the mash and am always close to set point, but I'm not that far in the mash. Anyway, I am more curious about this than wondering if my beer suffers.

I am getting a Bobby M. weldless thermometer solution to get some science to see what the difference is. I think a long term solution might be getting an RTD probe talking to my control box via quick disconnect to my tun. Does anyone do this, or am I over-thinking this?

 

[processhead]

You may want to score a digital cooking thermometer with a remote probe.

You can place it at various points in your mash to see what the actual temperature is.

On my RIMS, I put the RTD probe in the mash.

 

[burdbrew]

Yep, that makes sense. The end here is to run the RIMS direct to the mash temperature. Most setups I have seen put the sensor at the end of the RIMS tube, but this makes a lot of sense.

 

[acidrain]

Let me start by saying I use an insulated direct fired keggle MT.
My sensor is at the RIMS exit port, and controls the temp of the wort returning to the kettle.
My thoughts are that if you put the sensor in the mash, the return temp will be full blast until the temp comes up. I worry that return wort that is too hot will at minimum change the mash profile, or at worse, denature the mash.
I've experimented quite a bit with temp probe locations, and there is a huge difference in temperature at different locations in the mash. I've gone to stirring the mash via slow speed electric motor. This works really well at mixing and evening out the temps, but creates other problems with sucking grains through the FB.
Processhead, when mashing and the temp drops, have you measured how hot the wort temp is at the return port?

 

[mattd2]

If you get the Weldless thermometer look at installing in your MLT outlet, which should be the "coldest" part of your mash (as long as you are getting no channeling/deadspots).

 

[acidrain]

If you get the Weldless thermometer look at installing in your MLT outlet, which should be the "coldest" part of your mash (as long as you are getting no channeling/deadspots).

Is that what you do? What is the temp of the wort returning to the kettle?

 

[mattd2]

Is that what you do? What is the temp of the wort returning to the kettle?

No and I don't have a RIMS (yet). I didn't mean put the PID temp probe in the MLT outlet. I mean leave the PID temp sensor in the RIMS outlet, but also put the weldless (analogue) thermometer in the MLT outlet - then you have temp going into and out of the Rims tube.

 

[processhead]

Processhead, when mashing and the temp drops, have you measured how hot the wort temp is at the return port?

My MLT is a 10 gallon Rubbermaid round cooler. My RIMS tube uses a 4500 watt 220 volt element operating on 120 volts (1125 watts).

During upward temperature adjustments, the top of the mash will be 2-3 degrees hotter than the set point.

I am getting good conversion efficiency with my system, hitting my numbers, and have not noted any other evidence of denaturing of the mash enzymes.

 

[burdbrew]

So I ended up mounting a thermometer in my 70 qt Coleman Extreme Tun. I used a calibrated CDN digital thermometer with today's batch.

What I found was at the beginning of the mash I needed to turn up the RIMS to get my mash temperature up where I wanted it (4-5 degrees off), but before long, my mash temperature was drifting too high. I stopped messing around and parked the RIMS. I found that once temperatures evened out, my RIMS ran 1 degree higher than my mash temperature. Good enough, probably pass on further modification.