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JohninWV

Boiler Questions

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Operating pressure set on the controls on my boiler are 7 psi. The limit is set to 11 psi.

The pressure in the steam jacket of the still is 0.1 bar (so maybe 1.5 psi). My gate valve is only open 1/7th. But there's never a hiccup in the supply of steam. I always have plenty of heat.

To my limited knowledge, sounds like you're not getting enough steam moving through the system, or maybe too much. In addition to your gate valve, I presume you have another valve at the still to control the steam?

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I think it's just inconsistent supply as I have plenty of steam. I don't have a gate valve at the boiler just two gate valves at the still controlling flow and a pressure gauge.

Someone contacted me via email here and it seems that I need to change the purge times on the fan of my boiler.

Your boiler will cycle on and off to maintain temperature. Does that affect you flow rate? How much differential do you get in the pressure readings on the boiler?

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Yes, my boiler works in a similar manner. The boiler gets to steam pressure of 10 psi, and I think when it gets to 7 it kicks on and takes it back up to 10. I think the whole process from the moment the fan turns on until the pressure goes from 7 to 10 is maybe 90 seconds total. I'd have to check tomorrow to see.

But I never have problems with what's happening at the boiler effect my flow rate.

The steam at the still has the emergency blow off valve set at 0.6 bar (8.7 psi), and actual operating pressure in the steam jacket is closer to 1.5 psi. So even if the boiler was only at 5 psi, I would have lots of available steam.

I'm surprised that you don't have a gate valve at the boiler. When I first started running, I had the gate valve open further, and I thought it used a lot more gas to create the steam which was then just cycling through the system doing no useful work, so that's why I closed my gate valve down so much. Now the boiler uses just a therm per hour. So in this area, about $1/hour. Without a gate valve, it seems that the steam will go straight into the system, where it may not be needed at all by the still. If it's not needed, it'll go to your condensate return tank, and eventually back to the boiler. All for naught.

I'm not a steam engineer, so sorry I'm not being very helpful! Hope changing a setting at the boiler is all it is.

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Hey John,

Steam is always a tricky issue, especially when it comes to process steam.

It sounds like you don't have enough steam buffer for the settings you have on your boiler.

If you lower the differential (I would say 1lb is standard, but there are also 0.25lb) your boiler may keep the steam more accurate.

The problem is that it will then cycle on and off.

Gate valves are a good way to control steam if you have relatively steady steam.

The difference in psi you have requires either a large steam reservoir (more steam = more time for the boiler to start up) or a pressure reducer to keep your steam steady.

There are electronic options out there as well to counter severe drops in steam by modulation of a valve, but they are the most expensive solution.

As for residential vs. industrial - mostly the cost difference is cast iron vs. stainless, secondary shutoffs and so forth.

All the best,

Robert

Kothe Distilling Technologies Inc.

5121 N. Ravenswood Ave

Chicago, IL 60640

http://www.kothe-distilling.com

http://www.kotheconsulting.com

info@kothe-distilling.com

(312) 878 7766

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All you need to do is raise the PSI cap in your boiler. 10 psi is obviously too low given your steam demand. If you raise the settings to 14 psi, you'll have nearly a third more steam sitting in your boiler. Remember that you're going to have a pressure drop from the boiler to the still even if the pipework is well insulated. If you want a steady flow at, say, 7 psi when you're hitting your tails, you need to have the boiler sitting at a few PSI above that at all times....which means you either need to raise the psi in your boiler, or you need a larger reservoir of steam at 10 psi, take your pick.

As Mr. Birnecker suggested, I'd think about lowering the differential as well, but I'd try raising the the cutout first.

Your boiler tech will be able to do all of this for you safely, and he'll likely tell you the same thing.

Just one man's opinion.

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Todd,

I never saw your post...don't know why? Your posts are almost always spot on.

My boiler tech came by and put in a different card on my flame control. When the pressure drops below 9 PSI, the fan now only purges air for 30 seconds versus 90 seconds. It's perfect now. There's no noticeable change in the spirit flow at all. Another distiller here has the same boiler and burner and had the same issue and recommended it to me. Thanks to them!

BTW, we purchased some of your American Whiskey and some Blackberry Whiskey in Denver. Good stuff that's now part of my collection.

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I understand the answers may vary as much as the methods here, but do you all have a preference of brands of boiler systems and maybe contacts? Thanks!

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I understand the answers may vary as much as the methods here, but do you all have a preference of brands of boiler systems and maybe contacts? Thanks!

Your boiler is really the heart and sole of the operation. Do not skimp on quality. If the boiler goes down so does the business. We have a Burnham with cast iron exchangers. Coop

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Columbia. (Check their web site for dealers near you.)

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We have a "Smith" (7 x 100,000 btu).

I recommend on your water feed line be sure to have a spring loaded backflow preventer. The flapper style creates such a bang! If anyone remembers being here in my early days, you may recall it was loud enough to scare people.

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If things were equal, Two other small factors: 1) Be aware of which systems your installer/plumber is familiar with and can install efficiently. You do not want to pay for their education. 2)be aware of his relationship with the dealer. You can sometimes ask to share in on the discount a tradesman would get. Overall, as Coop pointed out, buy a quality product from a reputable dealer. You are going to ask your boiler to work many times over what a home heating boiler would do.

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Hi I'm trying to wrap my head around the use of steam for heating. I get the basics, boiler makes steam, steam goes through jacket, heat transfers, condensate returns to boiler. I'd like to understand the way you control your steam since obviously you need more or less at different points of your process. I'm reading in this thread (if im understanding it correctly?) about a common use of gate valves to control the flow of steam, with some presets on psi at the boiler to cycle it on/off to keep up with demand. Anyone know of any articles or diagrams to study to better understand this? I'm getting a bit confused at the moment, when I read of multiple valves used to control this? What is the function of each valve in the system design as opposed to opening one valve to let the steam in. Just having a hard time visualizing things from reading words instead of looking at a boiler system or diagram of one. Also wondering if this method of steam control (after adjustments for any assumptions or lack of understanding on my part) is the preferred method? So, manual control of valve(s), adjusted based on visual observation of temp gauges and output of still? I'm not interested in expensive motorized gate valves to do this for me, but (with my lack of a full understanding) I wonder about simple automation based on a set point controller telling the boiler go/no go from thermocoupler reading mash temp in still? My current thinking is it might work fine for the still but not so good for mash tun? Maybe to much problems with over shoot and such for that? If anyone has any thoughts for me, I thank you kindly! If anyone wants to let me pick there brain on the phone for a few on this one, I would thank you even more! Scrounge

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