Direct fire , e-rims, or pid control my stand?

I will be picking up my new brew stand this weekend from the gentleman that built it for me. This will be my first time brewing on a stand setup and my biggest goal is to really try to get a handle on controlling my mash temps so that I can recreate my recipes down the road.

I put a lot of thought into this and asked a lot of questions before passing the design off to my welder, but I guess the thing I never really thought of was the various methods or controlling temp on the recirculating mash. I designed the system to be direct fire and will be using my march pump to circulate water from under the false bottom back into the top of the keggle passing through a section of loc-line inside the keggle to control height of discharge (thanks BobbyM for that idea). I just assumed that when temp begins to drop I will fire the NG burner for a moment until the temp comes back up.

I am now being told by others that this will never work and by the time the thermometer catches up and I shut off the burner I will have over shot my mash temp. Is this really much of a problem?

This has started me down the road of looking at basic PID control for my unit. My first question would be that minus the automation, how is PID any better than manual control of the burner? PID would still fire the burner off and on based on the reading from the probe and therefore be subject to the same over shooting as I am being warned about?

If I did decide to add PID to control the NG burner, what is the simplest way to accomplish this? I've seen some pretty elaborate systems being controlled by brewtroller etc. I also remember seeing a stand a while back that was nothing more than some sort of hot water heater control module, a thermometer and a digital display without any sort of fancy controller. I must admit that when reading about PID control on the forums some of the wiring diagrams and such shoot over my head, so if anyone has an links to past discussion or demonstration of a basic PID controlled burner please let me know.

Lastly I could also still add an electric rims system. It seems from reading and talking with other brewers that an electric rims is the best for really controlling the mash temp. Is this true?

I've already bought and had the burner installed under the MT but there is nothing saying I have to use it. At the moment I have the budget to do whatever I need to do to make this work well within reason so I want to do it right. At the same time, if I sticking to my original plan of manually controlling the burner would work well enough then there is no reason to waste money.

What say ye?

No photos = no help... just kidding

PIDs learn (they will compensate to prevent spiking). We use them on some direct fire systems and they work fairly well. eRIMS with a probe in the tube and the MT is your best bet in my ever so humble opinion.

Members Kladue or day_tripper are probably the best sources for questions of that nature.

Thank you OneHoppyGuy, I just looked at your site - awesome stands! I will post pics of my setup when I pick it up this weekend. It's a 2 tier with HLT/MT on one level and gravity feed into the BK on the lower. I am running (hopefully not a mistake) the 10tip NG jet burners from Bayou Depot.

Do you have any photos of one of your stands under PID? If you don't mind sharing i'd like to see how you do it but I understand if you would rather not. Is it possible to just do a really basic pid where I just input desired temp without needing something such as a brewtroller etc? Not that I wouldn't mind having one down the road but for now if I could just plug in temp and let the control handle that it would be great.

What is the common way of putting electric rims in a keggle? I keep finding info for converting a cooler to a erims, any special considerations if it's a keggle?

Jon,
Thank you for the compliment. You most likely will not like the jet burners.

Neither of these photos are very good, but should give you a basic idea. There are a lot of very good threads on PIDs and building control panels.




Electric element in a cooler is a great idea. We use a RIMS tube from BrewersHardware (read $$$). We don't build with kegges or coolers only kettles, so if a customer requests we supply the RIMS, that is what we use.

Received some low quality pictures of the stand today. Sight glasses pending install + need to put a ball valve on the output side of the march pump. I also need to add the natural gas quick connect grill hose. The burners are also height adjustable because I could not decide if I really believed the 12" minimum distance stated by the burner seller. A big thanks to everyone who helped the past few weeks as I was putting this design together.