Charcoal mess on bottom of brew pot? Why?

[nedrierson78]

Over the past few years, I have been doing my full boil in my kitchen (on both NatGas and Electric). I decided to try my hand at doing the full boil in my garage with a LP tank and a new burner... So, the boil worked out great and boiled up quicker than I have ever done in my kitchen, BUT the boil kettle had a disgusting charcoal coating on the bottom after the boil was done. After cooling the wort I had one hell of a mess to deal with.

Can anybody comment on what caused this charcoal buildup on the exterior of my boil kettle?

How can I remedy this from occurring again (other than not using LP)?

Thanks for your input.

 

[Gentlemans_Ale]

If it was a new burner, it was probably all the paint and residue burning off. Make sure your flame is blue.

 

[nedrierson78]

Yes, It was a new burner.

Flame was mostly yellow.... Do I need to adjust something?

 

[Gentlemans_Ale]

Yellow flames will put off soot because it's cooler and not burning completely. Turn up the flame until it's blue and you won't have any soot - the hotter the flame the less soot.

 

[Bluelinebrewer]

My burner has a small round disc looking thing, that allows me to adjust the amount of air that gets mixed with the propane. You might look and see if you have one as well, it should be where the propane line meets the burner. Try turning it to let a little more air in. That's what worked for me, YMMV.

 

[thrashandburn]

While I too have this problem and have yet to remedy it, I've read that this occurs as a result of imbalance between air and propane as they flow through the burner. My understanding of it is that too much of one or the other causes the propane to burn with high inefficiency leading to unburnt propane sticking to the kettle and charring. Or something like that.

I have searched the internet for solutions myself and I can tell you that the advice that I have seen on various other forums are as follows: make sure the flame from your burner is as blue as you can get it. This is done by adjusting the air flow using the vent on the burner. It was also suggested that simply cracking the valve on the propane tank instead of opening it all the way will also aid in maintaining a hot, blue flame by slowing the flow propane to the burner. Some suggested that putting the kettle on a stand to raise it higher above the flame slightly will prevent this charring (though I have a feeling that this would make heating less efficient). Finally, I've heard it's an old trick to coat the outside of the kettle in soap to prevent the soot from sticking to the sides. Again, I have no personal experience in attempting any of these. However, these "remedies" I will be attempting myself on my next brew day, which sadly wont be for quite a few weeks.

 

[Bluelinebrewer]

Also, FWIW, I used to have this issue with my Wal-Mart special turkey fryer (it was cheap, and did what I needed). A few months ago, I purchased a Bayou Classic burner, and I have yet to have the issue. So, if you have the extra money, you might look at upgrading your burner.

This is the one I have: http://www.apexbrewwares.com/Beer-M...s/Bayou-Classic-SQ14-Outdoor-Patio-Stove.html

 

[desabat]

Had this exact same problem until I made some adjustments to my burner and my last batch didn't have any black sticky charcoal and was easy to clean. 1)Make sure your burner has the air vent opened correctly! Mine worked well with the air vent open fully but yours might be different. play with the vent on a low flame to test.
2)Play with the amount of gas needed to get a blue flame. For my first couple of brews I always tried to get a big vigorous boil by letting the flames go on high. But this isn't really necessary as I achieved a boil at the same speed by turning on the burner really low which gave a nice blue flame that came to a boil quickly enough.
Hope this helps!

 

[microbusbrewery]

Yep it's soot from incomplete combustion. Too rich of a fuel mix by not having the damper open enough is one cause. As others have said, open the damper more and see if that solves the problem. I ended up removing mine entirely on my natural gas setup.

Another cause is combustion gases not venting well. If you get nice blue flames without the pot on the burner, but yellow flames and soot when the pot is on the burner, then the combustion gases aren't venting like they should. This can usually be remedied by adding a spacer of some sort to lift the pot up off the stand a bit. On mine I welded some 3/8" round bar onto the stand and it works great.

P.S. Be careful, if it's producing lots of soot it's also producing CO. Make sure you're using it in a well ventilated area until you get it dialed in.

 

[PitRow]

just a little tip to make clean up easier, until you can get the mixture right. Before firing up the burner, rub a little liquid dish soap on the bottom of your boil kettle, it'll keep the soot from sticking as bad. Learned that a long time ago in boy scouts cooking over open flames.

 

[nedrierson78]

Great advice everybody, thank you. Going to try adjusting the burner and elevating the pot. Neither of which I have done.