RIMS and Mash

[nate456789]

Recently did my first RiMS brew using a RIMS tube. I had to watch the flow pretty close because the flow would slow down.
I used about a pound of rice hulls in a brown ale. Which normally would be over kill.
I am using a keggle with a jbird false bottom and a 1.5" RIMS tube from Bobby.
So I had to stir the mash every 15 min or so because of the flow rate would slow and I was concerned about scorching.
What are other RIMS brewers doing to keep your mash agitated and the mash from sticking?

Thanks

 

[stlbeer]

Reduce your flow rate on the outlet side of your pump. Sounds like you're pumping too fast and it's compacting your grain bed. RIMS or HERMS - this is a problem for any recirculating system.

 

[nate456789]

Reduce your flow rate on the outlet side of your pump. Sounds like you're pumping too fast and it's compacting your grain bed. RIMS or HERMS - this is a problem for any recirculating system.

I guess I am not too concerned about scorching I am running a 5500w ULD at 120v.
So having said that how slow are you running your flow rate?
Is it better to run it as slow as you can? Seems like a balancing act between keeping the heat up and not too fast of a rate to compact the mash.

 

[stlbeer]

It's a balancing act for sure. A 5500w element at 120v is 1375w. With it being an Ultra low element there's little chance of scorching your wort. I had initially set mine up the same way and never scorched wort in over 30 batches.

My flow rate is another thing. I don't have a meter on it and I haven't really measured the gal/min. I think I'm running the ball valve on the pump outlet about 25% open. Then if it compacts I'll close it further after loosening the grain bed.

 

[nate456789]

It's a balancing act for sure. A 5500w element at 120v is 1375w. With it being an Ultra low element there's little chance of scorching your wort. I had initially set mine up the same way and never scorched wort in over 30 batches.

My flow rate is another thing. I don't have a meter on it and I haven't really measured the gal/min. I think I'm running the ball valve on the pump outlet about 25% open. Then if it compacts I'll close it further after loosening the grain bed.

Thanks for the tips. I think I need run it a few more times to get a feel for it.
I was impressed with how it held temp and I was able to ramp up to close to mash out temps. Which I didn't think RIMS had enough output to do that.
When I started sparging with 200 deg water I leveled out at 168 in the grain bed.
I also wrapped my kegs with 3 layers of the reflective bubble wrap that I had left over from building my Pole barn. I am sure that helped.

 

[stlbeer]

Nice looking mash tun! I'm sure the insulation helped. I've got to do that....

 

[JayMac]

I've been reading a lot about RIMS setups as I'm looking forward to making my own, and I've heard a few people who have encountered your problem.

First, Once you've reached mashout temps, you should shut off your pump and heating element (if it doesnt do so automatically). Let it sit for 10 minutes (this will allow the grain bed to set by gravity). Now, when you turn on the pump, open it about 15%, and increase to about 25-30% if there is no restriction. From what I've heard, when lautering you don't want to open up the valve much further than that.

Hope this helps

 

[nate456789]

More pictures of the set up.

I have a 8" Temp sensor that reaches to right in the middle of the mash.
That worked out better than I had planned. I added an extra half coupler a little higher up so I can add another temp senor for bigger mashes

I am also using a 4" temp sensor for the RIMS tube.

 

[JayMac]

More pictures of the set up.

I have a 8" Temp sensor that reaches to right in the middle of the mash.
That worked out better than I had planned. I added an extra half coupler a little higher up so I can add another temp senor for bigger mashes

I am also using a 4" temp sensor for the RIMS tube.

Where did you get the adapters for the Tee's?

 

[nate456789]

Where did you get the adapters for the Tee's?

I got them from Bobby's site. Same price or cheaper trying to piece it all together.
I figure let him do the leg work and pay shipping once.
They are quality pieces too. No machining crap leftover to clean. Basically pbw and go.
http://brewhardware.com/rimsherms-parts

 

[luhrks]

First and foremost, you need to tell us the water:grain ratio you were using.

Given your setup and 1# of rice hulls I'm 99% percent sure that was the issue.

Frankly for a RIMS or a HERMS setup you really need to be running a 2.0-2.5 ratio(Quarts of waterounds of grain) or it just will not flow properly. Even then when doing a wheat beer, double up on rice hulls.

I do HERMS exclusively and every stuck mash I've ever had can be attributed to either too little water in the mash, or not enough rice hulls. More the former, than the latter.

 

[processhead]

First and foremost, you need to tell us the water:grain ratio you were using.

Given your setup and 1# of rice hulls I'm 99% percent sure that was the issue.

Frankly for a RIMS or a HERMS setup you really need to be running a 2.0-2.5 ratio(Quarts of waterounds of grain) or it just will not flow properly. Even then when doing a wheat beer, double up on rice hulls.

I do HERMS exclusively and every stuck mash I've ever had can be attributed to either too little water in the mash, or not enough rice hulls. More the former, than the latter.

I question whether this water/grain ratio is an absolute rule.

It is true that too little water can create problems, but I have been running 1.25/ 1 for years with good results and can't remember the last time I had a stuck re-circulation or runoff, which also includes grain bills with lots of wheat.

In my experience, what has been critical is to throttle the flow from the pump to keep from compacting the grain bed.

 

[JayMac]

I question whether this water/grain ratio is an absolute rule.

It is true that too little water can create problems, but I have been running 1.25/ 1 for years with good results and can't remember the last time I had a stuck re-circulation or runoff, which also includes grain bills with lots of wheat.

In my experience, what has been critical is to throttle the flow from the pump to keep from compacting the grain bed.

In this case, would you have the valve on the outlet of the pump partially open, and the valve on the MLT fully open? I think that's right, but just making sure

 

[processhead]

In this case, would you have the valve on the outlet of the pump partially open, and the valve on the MLT fully open? I think that's right, but just making sure

That's correct.
The suction side (inlet) of the pump should never be restricted.

The discharge side (outlet), should be throttled enough to control the flow. I usually will start with the discharge valve fully closed and then slowly open it till I get the flow rate I want.

I found through trial and error what works best on my system. At lower mash temperatures, I throttle the discharge valve quite a lot.

At higher temperatures approaching mash-out, I seem to be able to increase the flows, maybe because the viscosity of the mash is thinner at higher temperatures.

Other setups may vary from this a bit, but it works well for me.

 

[JayMac]

That's correct.
The suction side (inlet) of the pump should never be restricted.

The discharge side (outlet), should be throttled enough to control the flow. I usually will start with the discharge valve fully closed and then slowly open it till I get the flow rate I want.

I found through trial and error what works best on my system. At lower mash temperatures, I throttle the discharge valve quite a lot.

At higher temperatures approaching mash-out, I seem to be able to increase the flows, maybe because the viscosity of the mash is thinner at higher temperatures.

Other setups may vary from this a bit, but it works well for me.

Ok, that makes sense. Sorry for the thread jack, but I just have one more question about how you do your mash (at least it's relevant?)

So when you mash in, you pump water, then mix in grain. Let sit for 5 minutes so gravity can help settle the grain bed. Now, open MT valve fully, slightly open discharge valve (to get the pump primed). Turn on pump, and slowly open the discharge valve until desired flow is reached?

I haven't had a lot of experience with pumps yet, and I want to make sure I don't blow it on my first go when I finish my RIMS build in about a month haha.

Thanks

 

[processhead]

My method is to preheat water in my HLT and then I gravity feed the desired amount of strike water into my 10 gal Igloo MLT, using the volume graduations that are molded inside.

I check the strike water temp and if its needs tweaking , I will recirculate the strike water and adjust the temperature setpoint where it needs to be.

This has the added benefit of making sure the pump is primed and everything is working before actually dumping in my grist.

Now I stop the pump and add the grist. I don't do a lot of stirring, just enough to get everything wet.

I close the discharge valve and start the pump now. After the pump is started I crack the the valve enough to start the water flowing and get everything settled in.

When I am sure everything is flowing, I open the discharge valve further to get the flow rate I want for recirculating the mash.

I close the lid now and proceed with my mashing schedule until finished and ready to start the run-off.

As I mentioned in an earlier post, I start the mash at low flows until most of the conversion is complete and I am ready to start mashout.
At mashout I increase the flowrate, opening the discharge valve to aproximately 50-100%. If its a large mash volume, I will keep the mashout flow toward the 50% end of the valve setting. Smaller mashes can run wide open.

This procedure works well with my gear. Your mileage may vary.

Don't be afraid to do a lot of dry (wet?) runs with just water and your MLT so you are comfortable with how everything works.

 

[JayMac]

My method is to preheat water in my HLT and then I gravity feed the desired amount of strike water into my 10 gal Igloo MLT, using the volume graduations that are molded inside.

I check the strike water temp and if its needs tweaking , I will recirculate the strike water and adjust the temperature setpoint where it needs to be.

This has the added benefit of making sure the pump is primed and everything is working before actually dumping in my grist.

Now I stop the pump and add the grist. I don't do a lot of stirring, just enough to get everything wet.

I close the discharge valve and start the pump now. After the pump is started I crack the the valve enough to start the water flowing and get everything settled in.

When I am sure everything is flowing, I open the discharge valve further to get the flow rate I want for recirculating the mash.

I close the lid now and proceed with my mashing schedule until finished and ready to start the run-off.

As I mentioned in an earlier post, I start the mash at low flows until most of the conversion is complete and I am ready to start mashout.
At mashout I increase the flowrate, opening the discharge valve to aproximately 50-100%. If its a large mash volume, I will keep the mashout flow toward the 50% end of the valve setting. Smaller mashes can run wide open.

This procedure works well with my gear. Your mileage may vary.

Don't be afraid to do a lot of dry (wet?) runs with just water and your MLT so you are comfortable with how everything works.

Thanks for the detailed walkthrough. I like the idea of recirculating strike was to help prime and reach SP.

Is there any reason you don't pump the water into your MT?

Cheers!

 

[processhead]

If I made some minor changes to my plumbing I could pump from the HLT into the MLT .

My system is setup as a multi-tier layout that lets me gravity feed from HLT to the MLT to the BK to the CFC to the Fermenter.

My pump and heater are plumbed to recirculate the mash, and that's all that it does.

If I could figure out how to have gravity recirculate my mash, I would do that too