RIMS question

[garcara]

I recently built a RIMS system with a RIMS tube from BrewHardware. It's 120V only. The temperature probe is opposite the heat element in the tube. This seems like a pretty dumb question considering I already built the entire system and don't full understand how it works but, which end should be my input and which the output? It seems if the wort comes in on the heat tube then my temp will never get to the temp I set the PID to. It makes more sense to me to have the input go to the temp probe and then to the heating element. Just curious if there is a right/wrong or more common usage?

Thanks.

 

[thekraken]

Wort flows over the heating element, then over the temp probe, then back to the mash.

[Edit] The wort flows over the heating element and is heated a little bit, the temp probe reads the temp directly after it has been heated so the PID knows when to stop heating. Make sense?

[Edit] You can set up the temp probe where ever you want. I've been researching this a lot lately and it seems to be the consensus that it's best to control the temp based on the output. I've been thinking I would make my own PID controller and have a probe on both ends just for s**** and giggles.

 

[garcara]

If you take the temp on the output, you could never get to your temp though, the wort would have to be hotter on the output to raise the temperature in the tun. How is this effective?

 

[thekraken]

I do see what you mean. Everything would eventually equalize as long as your heat loss is small enough and your flow fast enough. With the probe on the output you could set your setpoint a few degrees above your target, and your grain bed may reach temperature quicker, you'd have to keep an eye on the grain bed temp.

With the probe on the input, by the time your input reached the right temp the top of your grain bed would be too hot.

What kind of controller are you using?

 

[thekraken]

I'd suggest you test it out and see what works best for you. Just throw some water in there and start recirculating.

Sous vide a couple rib eyes while your at it!

 

[helibrewer]

Mine is vertical, temp probe at top, element at bottom. The wort flows from bottom to top then to MLT. I do it this way for two reasons: 1) It insures that the element is fully covered with liquid at all times, even if the pump fails and 2) It measures temp at the output of the tube.

 

[blizz81]

I have mine set up per Bobby's instructions on the brewhardware page:


"Be sure your unit is filled with liquid (or better yet, get liquid flowing through) before you let your element energize. The unit can be mounted either horizontally or vertically, but for each of those, the wort in/out ports should be a certain way. If you go vertical, orient the element end down and pump liquid from the lower port up to the upper port. If horizontal, put the element end camlock port in the "down orientation" and use this as the input."

 

[garcara]

So wouldn't it be best to put the temp probe into the mash since that's where the temp is most important? Couldn't you plug one end of the tube and put the npt into the tun?

 

[helibrewer]

So wouldn't it be best to put the temp probe into the mash since that's where the temp is most important? Couldn't you plug one end of the tube and put the npt into the tun?

Too much latency, by the time your MLT probe was telling you the temp was good, the upper portion of the mash would be too hot.

It is not hard to figure out the heat loss between your RIMs and the MLT, then just use that differential in setting your controller...it's easy and is much more stable.

 

[garcara]

Too much latency, by the time your MLT probe was telling you the temp was good, the upper portion of the mash would be too hot.

It is not hard to figure out the heat loss between your RIMs and the MLT, then just use that differential in setting your controller...it's easy and is much more stable.

I am getting a better understanding now. It bothers me that I can't set my PID to the temp I am aiming for directly. I am going to install an analog probe in my tun and put the probe on the output.

Thanks.

 

[blizz81]

So wouldn't it be best to put the temp probe into the mash since that's where the temp is most important? Couldn't you plug one end of the tube and put the npt into the tun?

I'll say that with good flow, in my system (insulated keggle), with the "common method" of putting the probe on the out port, the difference between what I set my PID for and the (uniform) temp of my mash is pretty much always within 0.5*F - 1*F anywhere / everywhere in the mash. That's good enough for me.

 

[helibrewer]

I am getting a better understanding now. It bothers me that I can't set my PID to the temp I am aiming for directly. I am going to install an analog probe in my tun and put the probe on the output.

Thanks.

I get it, if we had steam jacketed MT's it would be a different story.

I use one digital sensor in the RIMs output, 2 digital sensors in the MT, and an analog thermometer on the MT output to the RIMs....between all of those, I determine my controller setting.

 

[atoughram]

If horizontal, put the element end camlock port in the "down orientation" and use this as the input."

Also, not sure if this is in Bobby's instructions, but if you install it horizontally, do not make it level. Make sure that the output side (Opposite of the element) is higher so that all the air bubbles flow out. I found this out when I got a scorched flavor but had good flow.

 

[byrone]

I am getting a better understanding now. It bothers me that I can't set my PID to the temp I am aiming for directly. I am going to install an analog probe in my tun and put the probe on the output.

Thanks.

Unfortunetly to monitor your mash and rims you need 2 temperature measurments. With my system I monitor my mash temp at the output of the mlt and monitor my rims temp at the exit side of the rims tube. I have the brewers hardware 2" tube with a 4500W element on 120V. My mlt is insulated so pretty much the temperature I set the rims tube to, the mash is as well. Worst case senario is that I have to raise the rims temp above the mash temp by 2 degrees. But this is usually only when it's cold out.

 

[blizz81]

Also, not sure if this is in Bobby's instructions, but if you install it horizontally, do not make it level. Make sure that the output side (Opposite of the element) is higher so that all the air bubbles flow out. I found this out when I got a scorched flavor but had good flow.

Yeah, I don't think that's in his instructions but a good point. I think by chance mine might be mounted very slightly off-level in that manner, figured it was a plus aiding on final drain anyways (though I generally unbolt and swing up and down a couple times for good measure).