Thursday, March 26, 2009

Thirst extinguisher

This is an old, but good, project that I built a few years ago. I retrofitted a commercial fire extinguisher to hold and dispense beer. I brew my own beer at home, so it is fitting to have a homemade "keg" to hold homemade beer!

The extinguisher tank is stainless steel, and fairly easy to clean. The top unscrews, and leaves a 3" dia hole. The extinguisher was originally setup to dispense fluid (ie it has a downtube that connects the outlet to the bottom area of the tank, and a port on the top for adding pressurized gas). This is exactly what we want to dispense beer. The main modifications that I made were:

Replacing the original (nasty) downtube with a new clean one
Replacing all of the rubber seals with new ones
Lots of cleaning
Added a low pressure gauge and compressed air quick-connect system (not shown in the photos)
More cleaning





I got my CO2 cylinder and regulator at a local welding supply store. It was expensive, and I am not sure if it was worth it.

In order to carbonate the freshly brewed beer, I keep the extinguisher in the refrigerator with the CO2 tank set for about 12 psi. I give the beer a vigorous shake once or twice a day, and after a few days or a week, it is ready.


The extinguisher is always a hit at parties, and has become a tradition.

49 comments:

  1. I stumbled across your blog and I must say, you have inspired me to build my own fire extinguisher keg. I brew my own beer and have a kegerator but this will be great to take on the road. Do you have any tips for building this? I actually was able to purchase an extinguisher almost identical to yours on ebay. sorry to be a copy cat but this is a great idea!

    jessica

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  2. Jessica, I'm glad the blog post inspired you to build another custom keg. I bought my fire extinguisher at a local scrap yard, but I think most stainless steel water-type extinguishers are the same, so you should be fine. Most of the work involved rigorous cleaning, and replacement of most of the O-ring seals in the main valve and downtube. The extinguisher had a port on the top for charging with air, and I replaced this with a fitting for my CO2 hose. Luckily, the port was 1/8 NPT, so finding fittings at a local hardware store was easy. Later, I added a quick-connect fitting like those used on shop air compressors and a better gauge. The original extinguisher gauge is just a prop -- its pressure range is not useful.

    I carbonate at about 13 psi depending on the style, and dispense at 3-5psi. Tell people to squeeze the handle slowly and have fun!

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  3. Thanks for the tips. I cleaned my extinguisher out yesterday and might make it to the store to get the stuff to put it back together tomorrow!

    Cheers!

    Jess

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  4. You should carbonate at 30-40 psi, rocking/shaking/sloshing for about a minute, right after you siphon into the extinguisher (room temp.). I do it every time, no measuring pressure, let it sit for a few days and it's good. Good to drink the next day if you don't mind cloudiness. Release pressure if it serves too foamy and leave the pressure down.

    Does that thing hold five gallons?

    Aaron

    A friend posted your link on my facebook. I brew also.

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  5. >You should carbonate at 30-40 psi

    You should not tell other people how to do things. Doesn't that fell good?

    Perhaps you meant to say "you can" or "you could"

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  6. What about ditching the CO2 cylinder once it's carbonated and using a more traditional pump as found in a keg tap?

    Also, how much does this thing weigh when full?

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  7. Anonymous, if I am in a real hurry to carbonate the beer, I might try it at 30 psi, but if I have a few days or a week (which I always do), then there is no reason to use a pressure higher than the desired equilibrium pressure. Search the web for a chart that shows CO2 volume vs pressure and temperature, then set the regulator according to your refrigerator's temperature and desired CO2 volume for that particular beer style.

    The larger of my extinguishers holds about 4.5 gallons, and the smaller one holds about 4 gallons. The weight of the extinguisher itself is very comparable to a Cornelius keg.

    It would certainly be possible to use an air pump for dispensing after the beer is carbonated. However, it's very easy to just take the CO2 cylinder along to parties and picnics. Set it and forget it!

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  8. also just a thought but you could use a smaller maybe 9oz paintball co2 tank for the dispensing i have a 20 lb co2 tank for home use and really dont like taking the large ass thing with me when i can take a few 9oz co2 tanks and have plenty of co2

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  9. Anonymous, I've seen very small CO2 (pocket-sized) in the MoreBeer catalog. They are pretty pricey, but very neat. I have a 5 lb CO2 cylinder, which is pretty easy to carry around.

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  10. Can you set up one of your fire extinguishers to dispense co2?

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  11. Anonymous, I am not sure what you mean. CO2 is a gas at room temperature/pressure, and when all of the beer is consumed, there is a blast of CO2 gas that comes out of the extinguisher. You can make solid CO2 (dry ice) by opening the CO2 tank upside-down and letting the gas expand rapidly and chill itself until it solidifies, but the yield is very low. It's much cheaper and easier to buy dry ice.

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  12. I guess my question was... if you have extra unused fire extinguishers can they be use for co2 tanks. What would you need to do so?

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  13. The fire extinguisher is designed to hold about 100 psi or less. You could store a relatively small amount of CO2 in there, but commercial CO2 tanks are designed to hold 750 psi, where the CO2 liquefies, allowing the container to hold 5, 10, 15 lbs or more of CO2.

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  14. Ben,
    I just came across a couple of identical fire extinguishers. I'm curious what you replaced the down tubes with. Thanks in advance - I'm going to have fun with this at the next brew club meeting.

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  15. Anonymous, I used acrylic tubing (about 3/4" OD). The fitting at the top of the original extinguisher downtube appeared to be ABS, so I bored a 3/4" hole, then used thickened acrylic cement to bond the ABS to the acrylic. Good luck!

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  16. Lovely idea. I've been carbonating for awhile; and my setup is a 24" fridge holding corny kegs (3). I run the CO2 in through the side (yep, I drilled it). I too paid $$ for my 10lb CO2 tank and regulator, but it paid for itself very quickly thanks to an add-on I made for everyone in the family: From the CO2 it runs into a 2 outlet manifold. One line goes to the fridge, the other to a length of hose and a tire chuck. With a modified pop bottle top (tire valve pulled through a 5/8" hole) I can carbonate anything: water, juices, even wine.
    Now, I love your idea and will try it when I come across one. Good for you.
    Andy

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  17. I have the same exact model fire extinguisher. Where did you find new seals? Particularly the main valve seal...

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  18. Beer Nerd, that's a good question. The extinguisher has two O-rings, a stem seal and a main seal. I believe the main seal is McMaster # 9452K172, and the stem seal is 9452K14. You'll have to double-check this by measuring the stem itself from the extinguisher and matching the O-ring inner and outer diameters. You'll probably find that the main seal is very deformed and doesn't even resemble an O-ring anymore. Good luck.

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  19. This comment has been removed by the author.

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  20. Cool... thanks for the quick reply. Yeah, that main seal is pretty squished and deformed, wasn't sure if it was just an o-ring or something special. I'll probably try to find them locally, as I don't order from McMaster unless I have a decent sized order.
    I'm thinking of trying a bike tire Co2 inflator for carbing and pressure.
    One more thing... do you mind if I post my build as a DIY article on my site? I'll give you a credit and link-back. The site is www.beer-nerd.com.

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  21. Ben, great blog! I picked up a very similar extinguisher at a yard sale today for 25 bucks and was researching some uses when I happened up on this site. I originally had in my mind that it would make a sweet mini "water" distiller boiler ;). After finding this though I think its purpose has been redirected. Beer Nerd, I also thought about the bike co2 inflators but I know those things are crazy expensive for the amount of co2 and are kinda small.. 45 gram is about the biggest? I've homebrewed a little in the past but know very little about carbonating and how much co2 is actually needed. I'm gonna research the paintball co2 tank option personally as I think it will be alot cheaper and pretty much just as portable.

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  22. Great idea. What size is the barb that the beer dispenser hose connects to?

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  23. Anonymous, I think it's about 3/8".

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  24. Ben, just picked up two extinguishers. Not sure what to expect inside. what did you use to clean these bad boy's. Do you really need to change out the pressure gauge. I would think that if your main gauge is set say to 10psi then there is really no need to switch them out, just mark on the original where 10 psi is etc.

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  25. bryon, the stock pressure gauge on my extinguisher would not read low enough for beer carbonation/dispensing pressures. Maybe yours does, so you can just leave it.

    I used hot soapy water to clean the inside of the tank along with a lot of scrubbing.

    Good luck!

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  26. Ben, Thanks for the info. I have not pressurized the keg yet. I soaked the kegs overnight with PBW and used my keg washer to wash them using oxy clean.
    My internal valves etc are pretty nasty. Where did you find new parts?

    Bryon

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  27. The stainless valve parts can be wire-brushed. The rubber O-rings can be replaced with O-rings from a local hardware store or McMaster.com. Good luck!

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  28. Ok thanks!! I'll give it a shot.

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  29. whats the part (and what size) called that screws onto the tire valve so you can connect a co2 hose to it? also whats that part that screws into the dispensor so i can replace the hose? thanks

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  30. Anonymous, this fire extinguisher has a normal 1/8" female pipe thread in the lid. You can buy standard 1/8" npt fittings at any local hardware store. I chose to put compressor quick-connect fittings on the tank for easy CO2 connections. The exit nozzle already had a hose barb, so I just bought some clear hose of the correct size and attached it to the nozzle after removing the original hose.

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  31. Ben, I got the same extinguisher but mine didn't have a dip tube going down the center, it just had a spring with a hard rubber washer holding in the piston. Where the piston/spring are has threads. Any ideas as to connecting a dip tube? Also, would you mind posting a picture of your co2 connection to the extinguisher? Thanks

    ~AL

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  32. AL, I had to replace the dip tube in my extinguisher. I cut the old one off, then used a lathe to enlarge the existing hole in the flange so that it matched the outer diameter of locally-available acrylic tubing. I then used thickened acrylic cement to attach the tube to the plastic flange in a way similar to gluing PVC slip fittings. If you don't have access to a lathe, try searching for nylon or silicone tubing that will fit over the outside of the flange, and just push it over, and cut the hose so that it reaches the bottom of the tank.

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  33. What kind of extinguisher did you use? make and model? Also would this work with an air pump. like used for bike tires.

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  34. Anonymous, the extinguisher is a General WS-700b. Using air as a propellent is not preferable because it will oxidize the beer and harm the flavor, however it will work.

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  35. Thank you, do you personally know of anywhere to purchase this type? or ones similar to it?

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  36. Unfortunately no. I went back to the scrap yard where I bought this one, and they had similar models that will work, but will be more difficult to clean since the top opening is much smaller. The scrap yard is the Alan Steel company in Redwood City, CA.

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  37. Hmmm ok, so would you recommend searching online for the model you have? Or attempting with a different model?

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  38. It's nice to have a large opening at the top of the tank. See if you can find one like that. Make sure it is stainless steel.

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  39. Think you could do something similar with an Aervoid container?

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  40. Thank you, do you personally know of anywhere to purchase this type?

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  41. It's my pleasure to see your post there i've looking for this topic for a long time and thanks God i found it now.

    Las Vegas Fire Extinguishers Sales & Service

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  42. Hey Ben, So stoked I found your blog. I just came across brand new stainless extinguisher. Never even been out of the box! 3 questions for you, First, The down tube, since it has never been used could I just use the one that came with it? or will I need to replace it with something else? Second, how do i install the quick connect system into the extinguisher body? And where can I buy one? Lastly, Do you recommend replacing the pressure gauge? Or would it be ok to see if the original one works first? Thankyou so much for posting this!

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  43. mike, check that the downtube doesn't have a lead weight at the end. Other than that, I'd think it would be OK to use. My fire extinguisher had an 1/8" pipe thread in the top, so it was easy to buy pipe fitting adapters and a quick-connect air fitting (often used for shop compressors) to setup the quick-connect system. The original pressure gauge has a range of 100's of psi, while we'll be serving and carbonating beer at 30 psi or less, so the needle on the original gauge will not move much, and not be very useful.

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  44. Awesome! Thank you for the help!

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  45. I have an almost identical fire extinguisher and I'm having trouble finding an appropriate fitting for the pouring tube. From what I can see, it's got 5/8 course thread. But of course, needing to use piping fittings, it appears to be a 3/8 MIP brass fitting. But most brass fittings have threads all the way to the flange, and the flange barely sticks out past the threads. Therefore there's no way to put a o-ring in place. I don't have a lathe to remove threads and some flange to make it fit properly. Any suggestions? I'd prefer not to have to glue stuff in.

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    1. The straight-thread pipe fitting (with O-ring) is less common, but can be bought online: http://www.discounthydraulichose.com/SAE_Straight_Thread_ORB_Hydraulic_Fittings_s/50.htm The real difficulty is finding a straight-thread pipe fitting with a hose barb for a nylon dispensing tube. I've never seen one for sale, but it may just take a long time searching on the internet.

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    2. I generally dislike online ordering of physical parts without technical drawings, so I went a slightly different way, the threads match 3/8" flare, which leaves space for an o-ring, The flare went to a 3/8" MIP so I got a 3/8" FIP to 3/8" Barb, bit of tape in between, all good. (Although I did have to cut ~1/4" off the flare end so I could actually compress the o-ring. Might have to get a slightly smaller o-ring for this setup, current one kind of bulges out since I couldn't get a square one.

      Second, my hand can't reach into the extinguisher to scrub, suggestions on how to clean the inside? Looks like just a little bit of limescale, potentially some old "LS-31 Keloy" or other antifreeze. I'm thinking maybe swirl vinegar many times

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  46. Hi Ben, Love this keg set up, ive made one and this is the first time kegging my home brew. im having an issue with just getting foam when squeezing the extinguisher handle gently, if i squeeze the handle fully i get good clear beer from the discharge tube but foams up in the glass really quickly. by the time its drinkable its flat. did you have any issues like this? how did you overcome only squeezing the handle gentle and only dispense the been nicely. ive reduced the pressure right down to only a few PSI (3-4psi) but still no change. any suggestions would be fantastic as this is the only sort of instructional how to use a fire extinguisher as a beer keg. Thanks appreciate this is an older post too.

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  47. I bet you folks were not aware of this. That same model of General Fire Extinguisher was located in the 2nd. Floor Lunch Room, at the Texas School Book Depository, Dealey Plaza, Texas on November 22, 1963.

    In fact, General made 3 similar models with the only difference being the type of chemical used: Foam, Soda Acid or Anti-Freeze (this one).

    You can see the reference images used for a very accurate 3D model of the Plaza here:

    http://dealey-plaza.org/this-government-as-promised/floor-2-lunch-room/Fire_Extinguisher/General_Fire_Extinguisher/

    -Ramon F. Herrera
    JFK Numbers

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