Direct Fire MLT scenario

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kegtoe

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Curently i have several vessels and i am alway changing my All Grain brewing. I guess i just like to mess around building stuff and tryin new things, ( and wasting money aparently :drunk:).

Anyway. I have 2, 10 gallon stainless pots. One i use as my hot liqour tank, the other i use as my boil kettle. i have a converted 5 gal cooler i use as mash tun. I also have an 8 gal electric kettle that i use RIMS style once in a while as my MLT. i have 2 propane burners - the 185,000 BTU bayou stands. They put out a lot of heat quickly.

I was thinking of going to a direct fire rims set up where i would add a 3rd burner and a 3rd 10 gal brew pot. I'm not sure why exactly i want to do this, other than asthetics (having all similar containers) and more pumping of the wort volume.

First, should i move to the direct fired system or just keep the systems i have. Second, if i do move to a direct fired setup should i do it rims style so i am always recircing my wort through the grains. and third, Would i want a less agressive burner? i heard some people say that the bayou burners are too powerful and not good for control.
 
If you go to the direct fired RIMS style system you should drop down to the 6" cast ring burner as the amount of heat needed is not much and the 10" burners would not be happy at that low level. Recirculation during heating is required with wort temperature leaving bottom of MLT used to adjust burner flame, and mash temperature monitored for step duration. A needle valve in burner gas feed is recommended for finer control as you close in on desired temperature if step mashing, or setup for intermittent firing to maintain temperature.
 
Kladue pretty much summed it up very well in a nutshell. Be advised that putting together and getting a direct fired RIMS to operate satisfactorily is not as easy as it would seem. I highly recommend automating the MT burner with a solenoid valve a la Lonnie's Brutus set up. Manually operating a RIMS burner requires constant attention and even then it can be tricky and tedious. A 6" low pressure ring burner would be an excellent choice for the MT. Avoid the multi-jet wok burners as well as the big banjo's for this application. The ten gallon kettles will be OK for 5 gallon batches, but too small for 10 gallon and larger batches. I think you will outgrow the 10's in a short time. I would highly recommend hooking up with someone who has an operating RIMS and schmooze him into letting you help him brew sometime. You will learn a ton from that experience and it will save you time and dollars in the long run. Lastly, go with a full width false bottom in your MT if direct firing and use a regular kettle instead of a converted keg if you can swing the cost.
 
How would a direct fire HERMS differ? Having your HLT direct fired, would your run more of a risk of unstable mash temps?
 
How would a direct fire HERMS differ? Having your HLT direct fired, would your run more of a risk of unstable mash temps?

I don't have any experience with a direct fired HERMS, but I'm somewhat familiar with the basic principle. There's more than one way to plumb such a setup. Some use a bypass loop so that only a portion of the circulating wort passes through the HEX coil and this can be adjusted either manually or with automatic solenoid valves. Others are built without a bypass and some of these systems automate the pump control. There are quite a few variables to consider such as the size of the HEX coil and the volume of the HLT etc., etc, not to mention that you would need to stir or otherwise circulate the HLT water to keep it moving over the HEX coil.

So, to answer your question, as usual I would say it all depends. I chose a direct fired RIMS primarily for it's simplicity. The direct fired HEX seemed like it would be more difficult to operate without a whole lot of automation. I only automated my MT burner with a solenoid valve and temp controller. Everything else is manually controlled.
 
Technically, what you are talking about IS a Direct-Fired HERMS system. The Wort is heated by passing it through a coil in a hotter liquid. Or are you pumping some of your wort into an empty kettle, heating it there, and pumping it back?

RIMS is very similar, but it heats the mash by passing it over a hot coil (Usually a water heater element)

Regardless, HERMS allows you to maintain great mash stability due to the huge thermal mass of the HLT volume. In other words, because the HLT is (let's say) 7 degrees above your target mash temp, it'll heat the wort while the wort tries to cool the HLT. Because the HLT thermal mass is large, it takes a lot of wort to bring its temp down because the relative difference in temp is only 7 degrees. (This is very similar to why ice is more effecient at the end of chilling - If you use ice when it's still 112 degrees, it melts very quickly)

The only down side is you'll have to manually chase the HLT temp with the gas regulator. (This is also why the Brutus was invented!)

Direct fire on the MLT is quite possible too, but I would think less forgiving than a HERMS because of the extremely fast temperature changes you can achieve due to the tiny volume of wort below a false bottom. I'm not sure I'd try it at all with a manifold down there - It would be really easy to scorch the grain that's laying on the hot metal.
I've seen it done (Can't find the thread right now) but it was automated. Again, it sounds like a lot of chasing the regulator to keep things in check.
 
From experience: a mash temp is extremely difficult to maintain through direct fired recirculation. I just ruined 10 gallons of stout because my thermometer didn't pick up the fact that my mash temp hit 180! I'm now going RIMS with a tube, PID, etc.
 
From experience: a mash temp is extremely difficult to maintain through direct fired recirculation. I just ruined 10 gallons of stout because my thermometer didn't pick up the fact that my mash temp hit 180! I'm now going RIMS with a tube, PID, etc.

I would disagree simply because a bad thermo can screw you with a RIMS tube as well... I direct fire my mash tun and control the burner with a BCS and I can hold +/-.5 F , but before I did that I did it manually and checked with 2 thermos and never had an issue.
 
I'd love to automate something but i dont understand electrical instrumentation for nothing. I dont know what SSRs do, i dont know how to program PIDs and i don't even know how wire all that **** together.

Also can someone recomend a solenoid for propane?
 
I'd love to automate something but i dont understand electrical instrumentation for nothing. I dont know what SSRs do, i dont know how to program PIDs and i don't even know how wire all that **** together.

Also can someone recomend a solenoid for propane?

I bought a gas solenoid valve from these guys:

http://www.valves4projects.com/servlet/StoreFront

Email them and ask them to recommend a specific valve. Their technical assistance is excellent and their prices are very good too.

FWIW, I'm getting excellent results with my direct fired RIMS. I have a solenoid valve (110v AC) operating a low pressure burner under the MT controlled with a Johnson A419. I monitor the mash temperature with a digital thermocouple thermometer. The thermometer probe is positioned in the grain bed. I circulate the wort as fast as possible using a full width false bottom. This setup is quite simple and straight forward. It didn't require a great deal of technical expertise to build. It basically operates much like a Brutus, but with only a single pump and an elevated HLT for a gravity fed sparge. The burner ignition is a standing Honeywell pilot burner (the dangerous kind without the thermocouple shut off).

I don't find operating my RIMS extremely difficult at all. Quite the contrary, but only after I automated the burner. Operating the burner manually was a major PIA.
 
From experience: a mash temp is extremely difficult to maintain through direct fired recirculation. I just ruined 10 gallons of stout because my thermometer didn't pick up the fact that my mash temp hit 180! I'm now going RIMS with a tube, PID, etc.

So, if your thermometer didn't register the 180 F, how did you know what the temp was? Were you operating the system completely manually?
 
I bought a gas solenoid valve from these guys:

http://www.valves4projects.com/servlet/StoreFront

Email them and ask them to recommend a specific valve. Their technical assistance is excellent and their prices are very good too.

FWIW, I'm getting excellent results with my direct fired RIMS. I have a solenoid valve (110v AC) operating a low pressure burner under the MT controlled with a Johnson A419. I monitor the mash temperature with a digital thermocouple thermometer. The thermometer probe is positioned in the grain bed. I circulate the wort as fast as possible using a full width false bottom. This setup is quite simple and straight forward. It didn't require a great deal of technical expertise to build. It basically operates much like a Brutus, but with only a single pump and an elevated HLT for a gravity fed sparge. The burner ignition is a standing Honeywell pilot burner (the dangerous kind without the thermocouple shut off).

I don't find operating my RIMS extremely difficult at all. Quite the contrary, but only after I automated the burner. Operating the burner manually was a major PIA.

I like the thought of using the A419. I have an extra one that i need to put to good use. I will try using mine with my electric turnkey fryer to control the heater in it. I have 2 wire mesh screens over the heater and then a bag in the whole unit so i dont have grains sitting directly on the heating element.

Is the temp probe on the A419 water tight? Do you have any issue using it in the mash??
 
I like the thought of using the A419. I have an extra one that i need to put to good use. I will try using mine with my electric turnkey fryer to control the heater in it. I have 2 wire mesh screens over the heater and then a bag in the whole unit so i dont have grains sitting directly on the heating element.

Is the temp probe on the A419 water tight? Do you have any issue using it in the mash??

I have the A419 probe mounted in a tee on the outlet side of my pump. The metal tip of the probe is in the wort stream flow, but not the junction of the lead wire and the probe tip. The probe tip is waterproof, but I'm not sure if the lead is. I highly doubt that it is. I used a 1/4" compression fitting to hold the probe tip. Instead of the metal ferrule, I used two small O-rings to make the seal. This works well and the probe is easily removed when not in use. I have the digital thermometer "k" type thermocouple in a thermowell mounted vertically in the grain bed. I let the thermometer govern as that is the actual grain bed temperature and adjust the A419 accordingly. I think you may have problems using your electric turkey fryer unless you can figure out a way to recirculate or continuously stir the mash. Otherwise the heat will not be unform throughout the grain bed. You are also likely to overshoot and undershoot the mash temps. It will probably be all over the place especially if you attempt step mashes or when ramping up temps for the mashout.
 
recirculating though my turkey fryer is not an issue :)

IMG_06091.JPG
 
recirculating though my turkey fryer is not an issue :)

IMG_06091.JPG

I like it. Looks like you are good to go. I do think that the platform on the left side is unnecessary, but maybe maybe I'm not understanding the setup completely. Now, get on with it! :D
 
It eliminates a little extra bending. i'm 6'7"

As you can see i have a really good blichman thermometer at the outlet of my pump but i find i have several degrees difference between the outlet of the pump and the mash.

Would you think a a419 would work or should i just watch my mash temps closeley? I have done a few AG batches through it and it has worked OK, but i need to get my effeciency better.

IMG_0636.JPG
 
It eliminates a little extra bending. i'm 6'7"

As you can see i have a really good blichman thermometer at the outlet of my pump but i find i have several degrees difference between the outlet of the pump and the mash.

Would you think a a419 would work or should i just watch my mash temps closeley? I have done a few AG batches through it and it has worked OK, but i need to get my effeciency better.

IMG_0636.JPG

IIRC, we had this exact same conversation somewhere in the recent past. You will always have some difference between the pump outlet temp and the mash temp. I do too. I don't have a clue about whether the A419 would work well with the electric kettle, but I don't see why it would not. It's certainly worth a try and you could always switch back to manual operation if necessary.

I would not be much concerned about efficiency. I generally get an honest 75%. It fluctuates some depending on how big the beer is, but I'm perfectly happy with it. You can get any efficiency you desire if you know how to manipulate the numbers properly. I see it done all the time.
 
i am revising my plans here. I have 3 - 10 gallon pots, 2 burners. I am now set on building a rims tube to control my mash temps. My plan is to have one burner for the HLT, the second for my boil kettle. Should i plan on a 3rd burner to get my mashes up to temperature a little quicker or do most of you jsut use the rims tube to bring the heat up for mashout?
 
i am revising my plans here. I have 3 - 10 gallon pots, 2 burners. I am now set on building a rims tube to control my mash temps. My plan is to have one burner for the HLT, the second for my boil kettle. Should i plan on a 3rd burner to get my mashes up to temperature a little quicker or do most of you jsut use the rims tube to bring the heat up for mashout?

That's the way the Sabco Brew Magic is set up. I would add the third burner. It would probably come in handy when heating the strike water, but also would help with ramping up temps as you mentioned.
 
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