Brew Kettle

[MarkKBC]

We recently purchased a used 7bbl system the brew kettle was made by Ripley stainless it is direct fired natural gas its all open under the kettle no baffles just open space. Our problem is the exhaust is getting way too hot we have piped it with 10" double wall insulated pipe but still gets way too hot can we maybe put a damper on it to slow the heat going up the pipe? It seems we are losing way too much heat up the exhaust. Your thoughts would be greatly appreciated Mark

[gitchegumee]

Oh god no! Don't put a damper on the exhaust of a gas-fired appliance! Had to take a nearly unconscious coworker to the hospital for carbon monoxide poisoning one day because our inner flue had heated to red, and the induced draft sucked the inner flue closed, constricting the outflow. Quite a scare. It takes days to unbind the CO from your system. Very bad idea. It would be worth it for you to get a qualified burner technician to adjust the system. That's my recommendation. Your life is worth it, I assume. Normally, any "damper" put on the system is called an atmospheric damper. It's basically a tee at the bottom of the flue with a swinging pie plate on the branch of the tee. This allows ambient air to be sucked into a long exhaust flue to cancel the buoyancy effect of hot flue gas. Keeps everything running at atmospheric pressure. That sure would have helped our crappy install way back when. But your system is open, so I doubt that would do much. A qualified technician could also determine whether your primary gas pressure is sufficient, whether your regulator is large enough, whether your secondary pressure is sufficient, whether your fuel/air ratio is right, and whether your flue is configured properly. You could easily pay for the technician with what you save in gas. And hospital bills. Good luck!

[MarkKBC]

Thanks for your help we have contacted a technician who is going to check the system out for us. I was told previous owner had a damper on the kettle but they were probably talking about the atmospheric damper you refered to. Cheers

Mark Goodwin
Finger Lakes Beer Company

[beermkr]

My DME kettle has a damper on the output of the fire box. What kind of burner do you have?

Mine is a forced air blower (Enonomite) and the manual for the system says to close the output damper 80%. It is one of the most efficient boiling kettles I have worked on so far. There is also an atmospheric damper in the flue pipe to help induce draft.

R/

[HinduKush]

My DME kettle has a damper on the output of the fire box. What kind of burner do you have?

Mine is a forced air blower (Enonomite) and the manual for the system says to close the output damper 80%. It is one of the most efficient boiling kettles I have worked on so far. There is also an atmospheric damper in the flue pipe to help induce draft.

R/

I've had two DME 15 bbl. direct fire kettles, same Enonomite burner, same damper, awesome design. Never had CO problems and monitored with a detector, never even spiked. The flow from the firebox was through the damper, 90 up, tee with barometric damper (described above), stack through roof. All flue pipe was Selkirk triple wall stainless with the exterior polished. Pretty standard...

[South County]

Installations

We are retrofitting a 7 bbl kettle and would like to get rid of the existing jet burner rings (constant issues) and convert it to a power burner like the Economites. Would anyone be willing to share installation pics, burner size, as well as burner box design and under kettle construction.

thanks
JR

[Guest]

We are also retrofitting a 7 bbl kettle, I would love to see some pics/info if anyone's willing to share.
Thanks

[cutter]

I am also looking to convert a 7bbl kettle to an economite burner. does anyone have any pictures of their burner setup and the flue design? Would super appreciate any info, thanks.

[Moonlight]

A barometric damper is critical in a flue when the draw from a tall chimney is too strong. This will suck the hot burning gases out of the firebox before they are done burning, causing high exhaust temperatures, which I have seen melt the lining of the flue ducting, making a nasty fire hazard.
The whole concept of a firebox is to:
1. make hot gases from the burning fuel/air mixture
2. allow the hot gases to linger long enough to transfer their heat to the metal surface of the kettle-ideally over as many square inches as possible (baffles help spread it around)
3. allow the exact right amount of the comparatively cool spent hot gases to escape up the flue so they can be replaced by fresh hot combustion gas touching the kettle bottom.
4. Not burn down any buildings or destroy equipment

I always recommend having a spot where you can see the burner in operation. Having this will allow you to understand and correct the gas quantity, burner location, and burner condition

[tcgore]

installation pictures

Was anyone able to get pictures of an installation to share? I am interested in seeing them.

Cheers,

Tyler

[cutter]

Anyone have any pics of the flue and the dampener? Would really be helpful for the internal side of the kettle. Im building mine out now and curious what is going inside between the kettle and the jacket. Appreciate any help! Thanks

[KaskaskiaBrew]

Here is a picture I took while at Colorado Boy Brewing School. He had an Economite burner underneath his 7bbl kettle. I don't have my kettle installed yet but hopefully this picture should get you started. I couldn't find a lot of information on the design of these fire boxes but here is what we ended up doing with the help of my HVAC guy and fabricator. We put a double liner of stainless steel under the kettle and used Ceramic Insulation between the liners. The pictures explain the concept better than I can describe it. Keep in mind that the pictures are just for reference and the flame inlet and gas outlet shouldn't be right across from each other unless you feel like blowing all your hot air straight out through the exhaust. We also added a sight glass so we can see the flame and removable bolts on the bottom so we can go in and check the insulation if we ever need to. Hope this helps.

Cheers,

[cutter]

Thanks, super appreciate it! What im looking to do is basically this. We have our boil kettle jacketed by another tank. There is a 5" offset or gap between the two tanks. Im planning to use 2" rockwool insulation on the interior of the exterior tank, leaving a 3" air gap to allow the hot air to circulate around the walls of the kettle. The gap on the bottom of the tank is 16" to allow the hot air/flame to have plenty of room to recirc under the kettle. There will be an exhaust flue and an access panel of course. Any suggestions or tips would be much appreciated. Just wondering if there any baffles or any other design features someone might recommend that might help as far efficient heating and exhausting. Also this is for a 7bbl kettle.

[KaskaskiaBrew]

I guess 2 concerns I would have, the first would be that the rockwool insulation isn't rated to a high enough temperature. I think the Economite recommended 2100F minimum temperature rating which is why we went with Ceramic insulation. The second would be how you would attach the insulation to the interior of the exterior tank. I'm not sure how you could keep the insulation from just falling back down into fire box. If it somehow did slide down into the fire box, you might have issues with the outside of the boil kettle being extremely hot because of the combustion air. I think you might be better off insulating the full 5 inches of kettle and then sealing off that insulation from the fire box. This will make your kettle more energy efficient and it'll keep you from having to worry about touching super hot kettle walls when you're next to it. I'm definitely not an expert at this so just it's definitely just opinion on my end.

Cheers,

[cutter]

Thanks again. You're correct on the insulation not rated to 2100F, its 1200F, ill go with the ceramic at 2300F. The insulation board i was looking at has wire mesh on one side which would face the kettle or air gap. With the ceramic board i might weld on tabs to attach too, or use a similar meshwire to press it into place against the inner tank.

Hopefully im not way off on this one. Ive seen other kettles that have similar designs (mostly user made of course) but looking for as much info and ideas as possible since im in the welding stage now. Just thinking that heat along the sides will definitely help with heating efficiency. I might try to go with 3" of insulation and 2" of air gap vs 2" insulation and 3" air gap after i try to run some calculations. Just seems like filling the whole 5" with insulation and not utilizing more space for heating would be less efficient on fuel cost in the long run?