Coffin cooling and other lessons I learned while building a keezer

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shroomzofdoom

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I am seeing a lot more coffin keezer designs on here recently. Thanks to innovative designs from many great HBT contributors more people are opting for the coffin box design versus the more common ‘through-collar’ design. A coffin keezer means more materials and more work time. For some this a small price to pay for a cleaner looking design.

This thread is not about kegerators, this thread is not about towers; this thread is about coffin style keezers.

I do welcome debate in this thread and hope it will serve to educate others. If you have any good ideas about how you solved the problem, please share. But let’s keep it specific to COFFIN COOLING as I feel that quite often, COFFIN COOLING comes up as a topic and people post solutions to TOWER COOLING. To paraphrase Don Rumsfeld; these solutions are ‘notably unhelpful’ to the coffin keezer crowd. I’ve taken all these detours and I want to prevent others from making the same costly mistakes.

The 10 degree differential hypothesis
I have conducted a number of tests with numerous different methods, probes, temperatures, and carbonation levels and found that first pour beer line foaming issues seemed to be resolved when there is no greater than a 10 degree differential between the coffin and the beer temp and also provided that you are already dealing with a balanced system. Though some CO2 will come out of solution with even a 10 degree differential, the impact is much less than if the differential is 20 degrees. If your beer is holding at 38; your beer line should be around 48 degrees; lower temps are even better. This is clearly subject to debate and I welcome input on this.



Following instructions online, I salvaged some PC fans and tried a few things. I even built one of those DIY tupperware container/PC fans setups. When that failed I tried the copper solution. While great ideas for tower cooling---again, these fell short when it came to cooling my coffin. I wish I had never tried them.

The only way I could keep from having foaming issues on the first pour was to back the pressure down to below 7-8. I am now able to run 11-12, fill a glass in a few seconds and the first and second pour are always the same.

My biggest mistake was basing my whole system around a very inefficient recycled PC fan, and a series of design errors based on that one single, underpowered component. When I asked someone for advice I was told ‘you don’t need much power in the fan that only a bit of air movement is needed’. When was ‘more power’ ever not needed in this hobby?!?! More on this later…

The first thing you should consider is the cost/complexity. Do I really want/need a coffin? Am I a good carpenter? Do I have the right tools? Am I able to do some minor wiring?


I am not an expert, but I did learn a lot at my own expense. I just hope this will benefit others going forward and that this will demystify coffin designs a bit.

So, let's get started...

 
Design Considerations
Coffin design-Plan out your coffin design thoroughly and take into account things like the length of the shanks, the air volume you are creating and how you will get air into and out of the coffin. Some guys go through the back for service, some go through the top. What works for you?


Lay out your shanks and connections and measure them, including the thickness of any insulation in your calculations. Longer shanks help if you can get the coffin temp down low enough as they will hold onto the cold for you and create more thermal mass, too long and your design is off; too short and they may not help. I went with 4 inch shank and these seem to work.

The freezer-Most chest freezers cool the walls of the freezer and conduct warm air to the exterior. I’ve seen a few chest freezers that have blowers. A blower freezer design would seem to be ideal in eliminating dead spaces, I just could not find any available.

Size Matters-The overall size of the coffin has a lot do with how you cool it. A larger air volume means that more air is needed to cool it. You can remove air volume by creating a smooth path for air movement and using closed cell foam built up into blocks to help channel air. Whatever route you go, cold air must follow a path, and is then exhausted back into the freezer compartment. Exhaust can be either passive (no fan) or active (fan-optional)

Air movement- There a few different ways of getting good airflow. Generally speaking, smooth, unidirectional flows are easier on the fan and are more efficient. A good design will also eliminate temp stratifications in the keezer and collar itself.

Take a look at the Jester369’s design. The air comes in one direction and then flows out the other end. Very efficient use of the fan and the cold air pathway design.
https://cdn.homebrewtalk.com/gallery/showphoto.php?photo=39875
https://cdn.homebrewtalk.com/gallery/data/1/medium/KeezerTopDetail4.jpg
(Credit: Jester369)

However Firefly765 also has the right idea. In his case, he pulls the air in through the fan and then exhausts it out through two holes.
https://www.homebrewtalk.com/f51/my-jester-clone-copycat-keezer-188696/#post2199404
(Credit: Firefly765)

My design also works and it stemmed from my original design idea of using a very small coffin and the fan--not only to move air into the tower--but to break up the coffin and keezer stratification. I found that I needed a real powerful fan to make up for the lack of a proper pathway and I had already donated my extra foam to a brewclub member. Even without this filler block I am able to reach my temp differential goal; which I am proud to say stands firmly at 7 or better. If the keezer is closed and the compressor has just been running, my differential is closer to 4-5. My shanks are also within the differential and ALL foaming is solved, seemingly at up to 15 PSI and with 12' lines. After that, I am pushing the beer too much.



(edit: that is the OLD crummy fan in that photo)

Insulation-If your design has a collar, insulate the collar with insulation panels that you can find in the siding section of your local home improvement store. These panels are cheap and can be easily cut and taped with foil furnace tape. Insulation saves energy, use it where you can. Be sure to insulate the walls of your coffin box too.



Collar Height (2x6, 2x8, etc) plays a factor in your overall design as higher collars will have much more dead space above the freezer walls. The taller the collar, the more air you need to move because of the longer distances and large volume of stratified air that tends to settle in the collar dead zone. This is because the walls of your freezer provide the cooling, the wooden collar does not.
 
Line length and beer balancing

I am not going to include any links to beer line balancing calculators; most have errors. Use them if you wish. I would have been better off just starting with 15’ of 3/16” line per tap. Most people I’ve spoken with have success with 12-15’ feet of line. Some need 20’. I needed 12’. Why? YMMV, nuff said.

Remember that your coffin is higher than a through-collar design by a few feet, more pressure is needed to keep beer flowing at the faucets. Adding a coffin and a collar as I did, makes this even more complicated. Though the calculators had fields for this, they didn’t seem to work for me and they were clearly off on calculating temperature stratification.

Ok, you have a new keezer and you are excited to finish the plumbing. Don’t cut all your beer line lengths at one time! Cut longer lines than you need and then trim them down as needed. (Thanks SweetSounds!) Only run one or two beer lines at first until you are sure the kegs are carbed and you’ve resolved any balancing/foaming issues. If you cut them all too short, you are going to need a new spool of beer line. (PM me if you want some nice 6” runs of beer line, super CHEAP!!)

I tried ‘adding’ 6 feet to a 6 foot line with SS couplers; the ID of the barbs are nowhere near as smooth as the ID of a beer line. This creates nucleation sites and the CO2 will have a tendency to come out of solution at the splice creating bubbles in the line. If you cut your line too short, suck it up and just buy longer lengths. If you have success splicing; let’s hear about it. Why do online brewstores even carry these?!?!?

Use threaded flare fittings and Oetiker clamps not barbs. You don’t need a special tool to be able to clamp Oetikers, just a dull pair of dyke pliers or nail puller pliers. (Thanks SweetSounds!) Oetikers are cheaper than worm clamps, look better, and aren’t going to cut you when you’re reaching into the keezer. I had some barbed fittings and sent them back. Oetikers/flare fitting fittings give you the ability to easily disconnect and reroute lines for cleaning. Barbed fittings will save you a few bucks but are more headache then they are worth over the long run.

Oh, and when you are buying your threaded fittings be sure to include the little nylon washers that go inside of them. (Thanks Dave!) I wasn’t aware that they weren’t included with the fittings—would have been nice to know that. The nylon seats ensure a leak free fitting at every connection and are very cheap. Like $2 for 30 or something silly. Get them.

Perlicks. Need I say more?
 
Coffin cooling

As mentioned above, the most efficient design for moving air through the coffin is by designing a smooth path for the air to move through. Simply put: air comes in one side and out the other. This reduces turbulence and allows the fan to completely vent the air in the raceway very quickly. The air must be blown through the path and have a place to exit.

If you have success with any of these methods--please post below and I'll edit the post.

Copper (passive) solution
https://www.homebrewtalk.com/f51/pvc-tower-cooling-solution-43072/
Great for towers, maybe not for coffins. No power required. This solution works GREAT for towers where the air volume is very small and the copper can be insulated. In my coffin, passive conduction with copper could barely get the temp around the beer lines over 50 degrees without air movement, way beyond my 10 degree differential goal.

The DIY or eBay kegerator cooler

airway_design_2.JPG



This did not move enough air for me and it created cold spots. Where the line exhausted, that tap was at 40 degrees, the one at the other end approached 50. It also seemed to restrict the airflow and stress the fan. Ultimately, I felt I could get better results by moving the fan to the coffin opening.

I was able to get a variant of this design to get the lines to my desired 10 degrees differential but only if I ran the beer lines inside of the air hose. The design also restricted airflow on the fan further. It was also too fiddly and I was never able to get my shanks cool enough. The fan should cool the shanks and they should also be within the 10 degree differential.

The ideal design-cool air in, air recirculates:
airway_design.JPG


All fans are not created equal. Thinking about saving a few bucks and using that PC fan salvaged from your old Dell? OK, it may work—but just know that most built-in PC fans have a very low CFM and very low ability to create pressure. The bearing design of cheaper fans means that may not be able to create much air pressure when under load –pressure is measured differently than CFM:

· CFM (Cubic Feet per Minute) rates how much air the fan moves in an unrestricted environment.
· Max Air Pressure, usually rated in ‘mm of H20’ indicates the fan’s ability to pressurize a column of water and to work against load.


Power supplies
You also need to consider the power supply in use. Most of us will salvage old phone chargers. Your fan and power supply have voltage ratings and an amperage ratings that you should be concerned with.

Fan Voltage is usually 12v. If you use a 9v charger on a 12v fan the fan will operate at roughly 3/4 speed. If you give it 12v, it will operate at full potential. Some fans vary speed by vary voltage input. DO NOT use a higher rated voltage power supply (e.g. >12v) than your fan is rated for.

Amperage is important, but your fan will draw only the amount of amperage it can use. So, your power supply CAN BE rated over the fan’s amperage rating. But using one that’s underrated is also not good either.

I went with 80 mm PC fans, but if you really want power go with a 120 mm. Just be prepared for some noise in either case.

This one moves 240 CFM and can create 27 mm of pressure:
http://www.newegg.com/Product/Product.aspx?Item=N82E16835213001
Whoa!

This one moves up to 84 CFM and can create 26 mm of pressure (and is a bit quieter):
http://www.vantecusa.com/en/product/view_detail/115
I use one of these, powered at 9v (probably pushing around 60 CFM) and it works for me. I wish I had this kind of info before I started this project. My loss is your gain.
 
Looking good so far, and this is valuable information.

Why not just use 115 volt fans to move air? You can wire it in directly without having to use an extra power supply. The one I have is 120 mm ball bearing design and pushes 110 cfm. It's main drawback is that it is fairly loud.
 
Why not just use 115 volt fans to move air? You can wire it in directly without having to use an extra power supply. The one I have is 120 mm ball bearing design and pushes 110 cfm. It's main drawback is that it is fairly loud.

Thanks for the feedback, I really hope the info helps some folks.

I actually looked for high CFM 80mm AC fans as an option, but couldn't seem to find any powerful ones. Most I was looking at needed 1 amp power supplies! I may not have been looking hard enough.

My power supply is DC 9v and 350 mA, and I didn't feel like finding another one (weird where we draw the line sometimes, eh?)

I was resigned to the fact that I was going to have to get a 12v, but when I hooked up my test fans to an adjustable power supply the sound of 12V @ around 120 CFM was...shocking. I still can't believe the amount of centrifugal force generated by the Vantec Tornado!

Are you using the 120mm AC for coffin cooling or is it actually cooling a PC/rack? How do you like it?

Good point though, for people that don't want to wire anything---an AC fan is a great plug and play alternative.
 
I'm using the fan in my keezer (conventional type with faucets mounted through the collar, no coffin), mounted on standoffs right in the middle of the lid, pointing down. It really moves the air in my keezer. But this is a far less tricky application than a coffin setup, from an airflow perspective. Still, I believe this fan would work really well in a coffin setup, especially if you push from one side and pull from the other. But it would be loud, unfortunately.

I chose the 115 volt fan because of the simplicity of wiring it directly into the existing wiring in the lid of the keezer. I wired it ahead of the light switch so it's on all the time. According to the label on the fan, it pulls .25 amps, so a little less than your 12 v fan. Of course, it's a lower rated CFM than yours too. But if you've got yours dialed down to 9V, it may be in the same ballpark.

This 115 volt fan and this 36 inch fan cord with molded plug to fit the connector on the fan.
 
Copper (passive) solution
https://www.homebrewtalk.com/f51/pvc-tower-cooling-solution-43072/
Great for towers, not for coffins. No power required. This solution works GREAT for towers where the air volume is very small and the copper can be insulated. In my coffin, passive conduction with copper could barely get the temp around the beer lines over 50 degrees without air movement, way beyond my 10 degree differential goal.

I'm in the process of building a keezer and using copper was going to be my plan of action. Could you expand on why you had such trouble with it? Did you encase the copper in insulation or was it open to the dead space of the coffin? I'm thinking that insulation will prevent a large air mass and keep everything within the 10 degree differential you've discussed. I've heard that others have had success with it, so perhaps others and expand on this discussion too.
 
I'm in the process of building a keezer and using copper was going to be my plan of action. Could you expand on why you had such trouble with it? Did you encase the copper in insulation or was it open to the dead space of the coffin? I'm thinking that insulation will prevent a large air mass and keep everything within the 10 degree differential you've discussed. I've heard that others have had success with it, so perhaps others and expand on this discussion too.

By all means, don't let me discourage you from trying. If you find this works for you, PLEASE let us know and I will edit my post above! I really want this thread to showcase ideas that work more than I want to be right!

I ran the bare 3/4" copper down into the keezer compartment about 6 inches and insulated the the upper foot or so with fiberglass pipe wrap insulation. The lower part of the copper was within acceptable temp range but it did lose temp the further up into the coffin it went. Without a fan at all the temp in my coffin would get up to 58-60 and the upper part of the copper was about 55 degrees. My floor/beer temps are around 40. So if I had to add a fan, then I might as well eliminate the copper.

Remember that in my case I also have a 2x8 collar design; keezers without a collar might have better luck due to better temp gradients.

Following Bradsul's thread, my thought was to modify this for a coffin you'd have to really insulate the heck out of the copper and virtually eliminate air space (foam board, great stuff, etc) so it sounds like you are on the right track. If you look at the successful implementation of this method in towers; it seems to work best with absolutely no air space. While this can be done with a coffin, I felt the fan worked better for me.

Let us know how you do!
 
I'm using the fan in my keezer (conventional type with faucets mounted through the collar, no coffin), mounted on standoffs right in the middle of the lid, pointing down. It really moves the air in my keezer. But this is a far less tricky application than a coffin setup, from an airflow perspective. Still, I believe this fan would work really well in a coffin setup, especially if you push from one side and pull from the other. But it would be loud, unfortunately.

My fan is very loud too, at 12v it's rated at 56 dBA, it's quieter at 9v but not much. Clearly fan drone is a drawback. But, whatever keeps the beer cold.:ban:
 
A Love controller like the TS-13010 could turn fans on and off as needed. That would eliminate noise when the fans were off and extend their life. But if the coffin won't stay cool for long, the fans will be on all the time anyway.

So has anyone tried using a small peltier cooler (thermoelectric) hooked up to a copper or aluminum plate in the coffin for the cold side and a finned and fanned heat sink on the outside of the coffin? It could be controlled with a Love.
 
Has anyone tried something like this in a 4" pipe that draws from the bottom and blows into the coffin? It's 120v. Just curious.

I was think of something like that or perhaps the guts from a nice (but broken) bathroom exhaust fan.
 
Last edited by a moderator:
Has anyone tried something like this in a 4" pipe that draws from the bottom and blows into the coffin? It's 120v. Just curious.

These tend to be pretty loud, but they do seem to have what it takes to move air. I think they can be gotten at Home Depot; as long as you don't mess it up, it can always go back. If it's an easier fit or a better solutuion--go for it. But please be sure to report back!

Though I would be remiss if I didn't remind you that the Vantec Tornado moves the same amount of air, in a smaller package, is quieter, and cheaper--you can get two of them for $25: http://www.ultimatepccooling.com/vato80fan.html


A Love controller like the TS-13010 could turn fans on and off as needed. That would eliminate noise when the fans were off and extend their life. But if the coffin won't stay cool for long, the fans will be on all the time anyway.

I borrowed this really sweet adustable power supply last week and was toying with all kinds of fan speeds and timed on/off cycles. For me, any time the fan wasn't on, I'd get stratification and dead air spaces. The coffin itself is a cold sink, even with a good layer of insulation--it's the weakest link in our design.

If the fan is cycling on and off then the in-coffin temps are varying, then the compressor needs to work that much harder on the next cycle.

With the fan on full time, the compressor goes through more cycles but they are shorter in duration. Then there's always the cost of another Love controller :rolleyes: One of those and I am halfway to a new fermentation cab

The noise is there, and I work all day about 10 feet from it...it's tolerable.
 
so shroomz, do you still have that copper? Willing to part with it for someone else to try their hands with it. I'll be certain to share my results.
 
Absolutely. I have a 3 foot length or so of 1/2" and probably even a few pieces of the fiber pipe wrap. PM me if you want to try it out...
 
Unfortunately, I haven't gotten around to completing the keezer yet. I've got all the framing done. Next I have to build a new lid/coffin and then I can begin fiddling with the copper. Unfortunately I don't have much time lately and this project is getting drawn out. I will post updates as they come though.
 
I dont have a coffin to cool, but in my other hobby (reef tanks) IceCap makes a line of nearly silent high cfm fans that run on dc. they come in 3 and 4 inch models and run 45-60 bucks on sale from various e-tailers. These are specifically designed to work in wet/humid environments and mine have survived years and years of working in salty, corroded areas without a hitch.

I know the price is sort of high, but If you replace a 20 dollar fan every year, these pay for themselves pretty fast. They have a variable speed temp. sensor, but this is for high end temp switching, so it would be counterproductive in keezer applications... I would just hang it outside.

Not sure on linking rules for other-than-brewing retailers, so just google IceCap fan if you want to read more...

**EDIT** looks like they have been discontinued, but there are a lot for sale at close out prices now.
 
I completed my kegerator with a coffin box a few weeks ago. I chose the 'simpler' method to start which was to encase the beer lines in copper right from the shanks and then down into the fridge about 10". I wrapped the joints with foil tape (so I could remove the whole setup if it doesn't work), then wrapped the copper with foam which I duct-taped in its entirety. To this point, I have drained a keg and a half and all seems well. The taps are cool to the touch though not cold, and foaming is not an issue. My kegerator is in the furnace room so it is not cool in there.

In conclusion, to this point I am not in need of a cooling fan.

B
 
This thread has been a good read. I'm about to start my keezer built, and I'd really like to do one with a coffin.

My first thought was aquarium fans too. I probably have an extra or two laying around, I'll have to give it a try and report back. May be a few weeks though.
 
I completed my kegerator with a coffin box a few weeks ago. I chose the 'simpler' method to start which was to encase the beer lines in copper right from the shanks and then down into the fridge about 10".

I think the 10" extension into the compartment is where your design might be substantially different to what I've tried...I just didn't have that kind of real estate, and also copper for six taps would have been rather pricey. One of the best PC fans I could find was about $15. The copper and insulation for my two tap proof of concept was around $20. Ultimately, this would have been around 3x the price of the fan setup for me.

I also found that the fan did a much better job of cooling for me. I used remote probe thermos to check the temp at the floor, collar/lid, top of coffin, and also at the shank. My shanks now are about 6 degrees off of floor temp, with the copper this as around 14 degrees. This improved my foam situation greatly, but it did not solve it---the first third of my first beer was always foam.

If the end result is NO foam, then you are all set! But please do share your design a bit more: photos, temps, collar/no collar, size of coffin, etc. Also, why would you go the copper route versus the fan?

As I mentioned earlier, I have every intent of modifying the original post as examples come up. But to do so I'll need some pics and details. Keep us posted and thanks for the input.




This thread has been a good read. I'm about to start my keezer built, and I'd really like to do one with a coffin.

My first thought was aquarium fans too. I probably have an extra or two laying around, I'll have to give it a try and report back. May be a few weeks though.


Thanks and please be sure to post photos and log your temps. The goal is to make this thread about the successful attempts and document the designs that work. I though of Aquar. pumps as well and they could fit the bill. If you have one laying around by all means go for it and post up your results.
 
I truly know how much effect a tower/coffing cooler can have. I installed a simple blower system in my Summit kegerator and it made a world of a difference. Runs full time and I used quick disconnects for the power so if the fan dies I can replace it easily and quickly.

BUT
In your design I have 2 questions.
1) The air movement in your diagram flows vertically up into the coffin, then has to make a 90 degree turn, flow across the shanks, make another 90 turn downwards and then flow back into the main keezer compartment. Forgive me, but this sounds kind of JFK'ish Kevin Costnerish in terms of efficency. Forgive me for mentioning his Waterworld name, lol. I shall not do it again. How much air do you feel coming out of the coffin area after it's made its journey?

2) How did you mount the fans horizontally to blow into/out of the coffin?

Your keezer is just awesome BTW. I just set up my buddies keezer using a tower and I showed him your keezer and his jaw dropped at what he COULD have had versus what he got.
 
I truly know how much effect a tower/coffing cooler can have. I installed a simple blower system in my Summit kegerator and it made a world of a difference. Runs full time and I used quick disconnects for the power so if the fan dies I can replace it easily and quickly.

BUT
In your design I have 2 questions.
1) The air movement in your diagram flows vertically up into the coffin, then has to make a 90 degree turn, flow across the shanks, make another 90 turn downwards and then flow back into the main keezer compartment. Forgive me, but this sounds kind of JFK'ish Kevin Costnerish in terms of efficency. Forgive me for mentioning his Waterworld name, lol. I shall not do it again. How much air do you feel coming out of the coffin area after it's made its journey?

2) How did you mount the fans horizontally to blow into/out of the coffin?

Your keezer is just awesome BTW. I just set up my buddies keezer using a tower and I showed him your keezer and his jaw dropped at what he COULD have had versus what he got.

Thanks for the kind words on the design. It had to fit into our overall design for the basement/bar area and look like furniture. Clearly A LOT more work, but it had to meet my fiance's seal of approval to get funding.
AS you can see, the base freezer that I used was downright fugly. I beleive someone referred to my work as 'polishing a turd'...lol
IMG_2875.jpg


If you look at the coffin itself, you can see that the fan simply fits into a small cutout in the insulation. It's an interference fit, no screws or sealant are used to hold it in. My coffin is 'rear entry' so I can remove the back panel to service the lines or replace the fan for any reason.
coffin.jpg


Regarding the overall design, mine is HORRIBLY inefficient. I guess that's sort of the point of my OP. If you look at the some of the others' designs I linked to, they are much more efficient. Ultimately...even an inefficient design will work. The keys are good air movement and unrestricted airflow. The air moves in one side and out the other and it's very brisk. I guesstimate that it's around 60CFM at the voltage it's running. There's no chance for air to pool or stagnate in the coffin as the entire air volume is probably changed 50 or more times per minute.

I hope this helps; if you have any other questions...let me know.
 
Gearing up to design a coffin setup - this is really helpful stuff. Thanks for posting.
 
I just took delivery of a Danby 10.2 cu. ft. chest freezer. It is a monster that can fit 8 corneys if I want. I will do at most six and probably 4 or 5 and use the rest of the space for fermenting lagers or storing ingredients.

I didn't do enough reading on this subject before I bought this thing and perhaps this has been answered else ware but, how are most people attaching the hinges and where are they attached? Does the flat table top flip up or does the whole thing collar includes raise up? I could see advantages to the whole thing lifting up but I wonder how I find hinges that will deal with the weight.

I used 2x6 to build a basic collar and have the original top resting on it now. In the future I was planning on "padding out" the 2x6 collar with some 1/2" thick nice looking wood so it looks better and will go flush with the outside edge of the freezer. This is kind of hard to describe with out pictures.

Ultimately, I would like to build a cooled tower/coffin top with 4 - 6 taps and room for up to 8 taps. I would like the table top to have some glass tile on it or something nice looking but the weight of this thing fully loaded with taps, wood, tile etc. and lifting that up and having it stay up while I switch out kegs kind of scares me. Any suggestions of parts (hinges especially) would be appreciated.
 
how are most people attaching the hinges and where are they attached? Does the flat table top flip up or does the whole thing collar includes raise up? I could see advantages to the whole thing lifting up but I wonder how I find hinges that will deal with the weight.

Mine is designed more or less like a car hood with a piece of 1x2 as a 'prop'..

Some guys do design it so that the collar lifts up with the lid. They seem to be most concerned with lifting cornies in over the higher collar. Lifting the weight of the lid/collar/coffin assembly seemed to be too much for the OEM freezer hinges to me. Plus I wanted more a finished look. Having the door break in the middle of my panels just wouldn't look right.

In my case, I simply detached the original lid and spring loaded hinges from the freezer compartment. I then glued my 2x6 collar to the freezer body with a healthy bead of silicone (no screws) The original lid and hinge assembly was then just mounted to the 2x8 collar with sturdy 1 1/4 inch screws. The surface of the keezer, along with the coffin, simply lift up and get propped with the 1x2 while loading/unloading.


I used 2x6 to build a basic collar and have the original top resting on it now. In the future I was planning on "padding out" the 2x6 collar with some 1/2" thick nice looking wood so it looks better and will go flush with the outside edge of the freezer. This is kind of hard to describe with out pictures.

I think I get what you are going for--more of a 'finished' look. You can use wood to finish out the collar-no problem. Just pay attention to the freezer's specs regarding sidewall clearances. In my case (above in the thread) I went with finished panels that are easily removable and mounted to the face with small screws. This works perfectly with my freezer's recommended sidewall clearance of only 3/4".

Hope this info helps, congrats on your decision to build a keezer--you won't regret it.
 
Thanks for the info. Now I'm off to find some nice looking 1/2" plywood to go on top of the 2x6. I will also get some kind of table top instead of the original lid. I am thinking of getting some copper sheet metal for the bar top but we'll see how much it costs.
 
Thinking about how a freezer cools (from the floor and walls), I would think that ducting the cold air supply from the bottom of the keezer (room permitting) would be optimal. A small section of drier exhaust hose.

From an air movement standpoint, which would be more efficient, attaching the fan to the low end (pushing the cold air) or at the base of the coffin (pulling the air)?
 
Thinking about how a freezer cools (from the floor and walls), I would think that ducting the cold air supply from the bottom of the keezer (room permitting) would be optimal. A small section of drier exhaust hose.
The bottom is where the coldest air is, no doubt. My experience was that I just couldn't move/direct enough air to keep all of the shanks at the right temp. The one nearest the cold output would be quite cold, but further along the row, the temps varied. I tried using wyes to aim and direct it and wound up with something analogous to a 'tubing octopus'

I think that 'room permitting' is the most important aspect. A hose when cold is very brittle and hard to position and move. Plus, the box wastes real estate that could be put to better use.

By simply placing a high volume fan where the coffin meets the lid, I was able to do away with hose, box, and octopus and fit another keg. To me, this just seemed easier than dealing with the alternatives.

If you are able to get it working, please record your temps and post back here. I wouldn't want to dissuade anyone from trying things, the original post was about showing the shortest (and hopefully, cheapest) route to solving this problem.
 
My thought was a center hole design with a "Y" into the coffin. The main fan would be an in-line duct fan as one of the posts mentioned earlier. Two return holes to either side (with or without fans) creating sort of a rams horn or turbo-charger effect.

All this packed in and routed as you any number of the other builders have done in closed cell foam. I will post the design as I build and complete it.
 
shroomzofdoom said:
The bottom is where the coldest air is, no doubt. My experience was that I just couldn't move/direct enough air to keep all of the shanks at the right temp. The one nearest the cold output would be quite cold, but further along the row, the temps varied.

To an extent this isn't an undesireable effect if you ask me. Different beers and other beverages serve better at different temperatures. I don't have the link handy but I believe light ales serve best really cold, while lagers and stouts are best served 10-15 degrees warmer. If you were so inclined you could take advantage of different shank temperatures in your design by serving the beers progressively darker etc.

Keep the thread going, I'm about to embark on my keezer build soon with a coffin in the basement and a chilled line to the kitchen taps I plan on mounting a floor above.
 
To an extent this isn't an undesireable effect if you ask me. Different beers and other beverages serve better at different temperatures.

If there are no stratification or dead zones in a keezer, all the kegs will serve at roughly the same temp. Generally, the temp that's on the floor +/- a few degrees.

The issue with coffins is that the warm air rises, making the coffin the warmest spot--sometimes a 20-25 degree difference from the floor. If the shanks are not cold enough or the beer in the lines is warm, the first pour of every beer will be mostly foam as the gas comes out of solution at the warmer temps.

A fan breaks up this stratification, and also allows the shanks and lines to remain consistently close to the temperature of the beer in the kegs--this will result in less foamy pours--whether it's the first or last beer of the day.
 
I got a lot of helpful info from this thread, thanks shroomzofdoom.

If your going with a coffin and a collar I would think that a fan would be mandatory to get rid of that warm area at the collar. Then insulating the heck out of your coffin, leaving just enough room for the lines should give you respectable temps. There is very little beer in a foot of 3/16" line.

I almost went with a fan in the keezer to eliminate any cold spots but my temps were good enough for me.
 
Something I'd like to add, if you want to edit it into the OP it would be worth pointing out. Be careful of the bearing in the case fan you decide to go with. Sleeve bearings are not meant for a horizontal position. If used horizontally, the will be much louder, and last generally only a month or two. For Horizontal use, make sure your bearing is a ball or fdb bearing.
 
Subbed... Just about ready to modify my keezer and tips like this rock. Thanks!
 
I have started a 3 ring binder from various builds basically from Jester369 design. However I want to scale up to a 25 CF freezer and I have a 2X8 collar, basically because I wanted to use the original hinge attach holes (7" apart). I would like to get my hands on the Google Sketchup plans so I can scale it up to fit my size, plus an area on the side for my gas tanks (outside freezer but inside coffin base). Parts are not too hard to figure out but the base/frame is where I get lost. Any design plans that can help me would be appreciated.
Thanks in advance,
Mike
 

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