Barnwood Keezer

[DurtyDawg]

After a blitz build the past several weekends my Keezer is done. I still have to finish the plumbing which I will convert to John Guest fittings for quick disconnects and switching between Taps. I got many ideas from this forum. I ended up adding a collar to my
10CF Freezer and coffin top. Freezer will hold six 1/6 barrels and room for a nitro and separate CO2 setup.

View attachment ImageUploadedByHome Brew1430941221.853557.jpg

 

[MrE_the_Great]

Looks amazing, way to go! One question, are you worried about heat exchange from the outside walls of the freezer with everything covered? My freezer is being delivered Saturday and I still have so many ideas to narrow down. Congrats!

 

[DurtyDawg]

Not worried. I may not cover the sides of the Keezer directly with plywood. I've read and seen some things on here that are way overkill. I like the KISS principle. Ensure the compressor section is vented and you'll be fine.

 

[BrooklynTom]

Very cool. I like the use of the barn wood. Also the use of both collar and coffin, good idea. Lots of luck,and enjoy.

 

[DurtyDawg]

I used tin from a barn for the top and backsplash. Here's a schematic to rewire the thermostat I found on this forum. It really was easy. The hardest part was pulling the new thermometer lead through the bottom of the freezer. It's an Inkbird which reads in Fahrenheit.

I've included some more pics to help others as I'm cleaning out my photos box.

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[jbb3]

Looks awesome! You'll love those flow control faucets.

Now get to brewing and fill it up!

 

[MusicalBrewer]

I used tin from a barn for the top and backsplash. Here's a schematic to rewire the thermostat I found on this forum. It really was easy. The hardest part was pulling the new thermometer lead through the bottom of the freezer. It's an Inkbird which reads in Fahrenheit.

I've included some more pics to help others as I'm cleaning out my photos box.

View attachment 276443

I am currently building a keezer and thinking of doing a very similar design. Does your coffin stay cold enough to prevent foaming? Do you know the temp difference between your coffin and the main keezer?

 

[Elkobrewer]

Looks awesome.

 

[DurtyDawg]

I have two fans going and two inches of dense foam insulation insulation. All joints were caulked there is a 15 degree difference and I get foam on first pour. Flow control taps fix that but still not wanted

 

[TheMadKing]

This is almost exactly what I want to do. Awesome build!

 

[brewerJase]

One of the nicest keezers I've seen on here. Nice work.

 

[DurtyDawg]

Thanks Buddy. Fun build.

 

[MusicalBrewer]

I have two fans going and two inches of dense foam insulation insulation. All joints were caulked there is a 15 degree difference and I get foam on first pour. Flow control taps fix that but still not wanted

Wow...totally not what I expected to hear. I thought for sure the temp in the coffin would be cooler. Looks like I might have to rethink my design.

Thanks for the reply! And your keezer does look awesome!

 

[d_rock]

I have two fans going and two inches of dense foam insulation insulation. All joints were caulked there is a 15 degree difference and I get foam on first pour. Flow control taps fix that but still not wanted

Is this beer temp in the glass, or monitored temp inside the coffin box? It's expected for a warmer beer glass and air temp to raise the poured beer temp, but the coffin should be closer if its insulated well.

 

[DurtyDawg]

Monitored inside the coffin top. The only way I can think to improve the temp difference is to buy new fans with a higher CFM rating

 

[d_rock]

Monitored inside the coffin top. The only way I can think to improve the temp difference is to buy new fans with a higher CFM rating

I'm guessing you have one fan blowing in, one out? I wonder if it would make a difference to only use one fan blowing in, to maybe prevent the cold air from being "pulled" out by the other?

I'm curious to see what my temp differential is as my setup is very similar to yours. I'll take note of fan stats as well.

 

[DurtyDawg]

Hmmmm. Worth a try and easy to do. I'll let u know the results.

 

[thumpersk_a]

Very nice keezer. One thing i regretted was i used the same caster wheels and they bought the farm shortly after the build was complete. Get 3-4 kegs, co2, nitro tank it gets heavy fast. Might save you a headache later.

 

[DurtyDawg]

AGREED!!! I was trying to keep the build height as short as possible. I saved 2" by using the smaller wheels. It's hard to move the Keezer when full of kegs. I'll jack it up and put bigger wheels on it at some point.

 

[jbb3]

I have two fans going and two inches of dense foam insulation insulation. All joints were caulked there is a 15 degree difference and I get foam on first pour. Flow control taps fix that but still not wanted

To keep the CO2 from coming out of solution due to difference in temperature, you need to have less than a 10 degree differential between the keezer and the coffin top. Probably could use some fans with a little more umph.

I used 4" duct fans with a variable speed control and a false bottom/snorkel to pull the coldest air from the bottom of the freezer and circulate through the coffin top. I have to keep the fans turned down or the taps sweat from condensation because they get so cold.

Take a look through the Coffin Top Keezer Build thread link in my signature and maybe it will give you some ideas.

 

[MusicalBrewer]

I'm guessing you have one fan blowing in, one out? I wonder if it would make a difference to only use one fan blowing in, to maybe prevent the cold air from being "pulled" out by the other?

I'm curious to see what my temp differential is as my setup is very similar to yours. I'll take note of fan stats as well.

I'm still in the process of building the coffin for my keezer (the shell is done, but the inner workings are in process). My setup is nearly identical to DurtyDawg's with two fans on the side and a hole for the beer lines in the middle. I did a mock up tonight and was very pleased with the results. I have two 80mm CPU case fans, one drawing air into the coffin, and one blowing out. The one drawing air in is connected to a 1 1/2" diameter hose that goes to the bottom of the keezer. The temperature in the coffin ranged between 3-5 degrees warmer than the temperature in the keezer. The temperature probe for the keezer is located in the center (measuring by height).

My insulation is far less than DurtyDawg's. I have 2 layers of 1/2" insulation in the coffin. The coffin is relatively small though. The space that needs to be cooled is approximately 11" wide x 12" tall x 3" deep. Those are the measurements of the open space in between the insulation. My fans are rated a 24 cfm air movement.

Based on this I don't think turning one fan off would make the difference. I'm thinking a small space to cool and drawing air from the bottom of the keezer are the two key elements.

I don't know how to insert a link to my build, but it is titled "Building 2 keezers at the same time". I'll post some pictures and more data there this weekend if anyone is interested.

Did you get any temperature readings on your keezer d_rock?

 

[d_rock]

Did you get any temperature readings on your keezer d_rock?

Not yet. I haven't had a chance to complete the final assembly. I'll get some spare time this weekend and will get it together then, I'll be sure to post temps and also my fan specs.

 

[DurtyDawg]

MusicalBrewer. I agree with you that the key to keeping to coffin top cool is drawing the air from the bottom of the Keezer. I could add a hose to fix the problem. Good luck with ur build. I've run probably 20 kegs through mine since last summer. BTW, John Guest fittings for quick disconnects are awesome when you need to clean beer lines or swap taps although getting the right size fittings is a pain in the ass.

 

[MusicalBrewer]

I'll check out those John Guest fittings...I'm in to making life easy!

Thanks for the reply's and letting me hijack your thread for a bit. The information was beneficial!

 

[rwc_617]

Durty, do your coffin fans run 24/7 or are they slaved to the compressor power? I plan to build a similar keezer and plan to run mine fans 24/7. Very surprising that two fans can't get the coffin temperature any lower.

 

[DurtyDawg]

The fans run 24/7. I'm not sure the CFM. They are 5 inch fans I believe.

 

[DurtyDawg]

Check out this guys thread for the John Guest fittings.

https://www.homebrewtalk.com/showthread.php?t=517311

 

[d_rock]

Did you get any temperature readings on your keezer d_rock?

Sorry for the delay, but I finally got my keezer back together and was able to monitor the temps. I set my ITC1000 to 40F, and the coffin stayed between 50-51F. This is using a single 4" PC fan blowing upwards into the coffin, with four 1" return holes. I am planning to rig a PVC duct to reach the bottom of the keezer floor to pull colder air to the coffin, for now. My ultimate goal is to build a better air circulation system for the entire keezer, using a raised floor grate to keep the kegs 1-2" off the floor, and one or multiple fans mounted low to circulate cold air upwards, including a more permanent duct into the coffin box.

My keezer lid and coffin box are not insulated any more than two layers of wood provides. The lid is 3/4" plywood, with 3/4" pallet wood on top, framed by 2x4. The inner surface is sealed with rubber spray undercoat. The coffin box is 1/2" plywood with 3/4" heart pine on the outside, also sealed by the rubber spray undercoat. This will do for now but I do intend to insulate both the lid and coffin with 1/2" foam panels to hopefully minimize temp loss.

 

[d_rock]

I'm still in the process of building the coffin for my keezer (the shell is done, but the inner workings are in process). My setup is nearly identical to DurtyDawg's with two fans on the side and a hole for the beer lines in the middle. I did a mock up tonight and was very pleased with the results. I have two 80mm CPU case fans, one drawing air into the coffin, and one blowing out. The one drawing air in is connected to a 1 1/2" diameter hose that goes to the bottom of the keezer. The temperature in the coffin ranged between 3-5 degrees warmer than the temperature in the keezer. The temperature probe for the keezer is located in the center (measuring by height).

My insulation is far less than DurtyDawg's. I have 2 layers of 1/2" insulation in the coffin. The coffin is relatively small though. The space that needs to be cooled is approximately 11" wide x 12" tall x 3" deep. Those are the measurements of the open space in between the insulation. My fans are rated a 24 cfm air movement.

Based on this I don't think turning one fan off would make the difference. I'm thinking a small space to cool and drawing air from the bottom of the keezer are the two key elements.

I don't know how to insert a link to my build, but it is titled "Building 2 keezers at the same time". I'll post some pictures and more data there this weekend if anyone is interested.

Did you get any temperature readings on your keezer d_rock?

@MusicalBrewer - Here's my final setup. Nothing fancy at all, I put a 4" PC fan in the tower pulling up, and another 4" fan in the floor of the keezer (I used long screws as posts to keep it 2" off the floor). With just the coffin fan, it kept temps 10-12 deg higher than the freezer temp. I decided to add the second fan in the freezer floor and it seemed to help, it dropped the coffin temp by 2 degrees. Now I'm seeing just under a 10 degree differential between coffin/freezer on average. I'm using Perlick 650SS and 10' of beer line, so any foaming issue is pretty much negated by the equipment, but the cold lines are going to keep that beer in the line fresh.

I plan to make a new keg floor/PVC duct system eventually that will better circulate air in the keezer, and hopefully reduce some condensation issues I'm having.

 

[DurtyDawg]

Why not try to layer a couple more layers of foam around the coffin to see what that will do to ur temps? I like ur setup.

 

[rwc_617]

@d_rock, the area of a circle is pi*D^2/4, so your 4-in-diam input fan has an inlet area of 12.57 sq-in, but your four 1-in-diam exit holes only have a combined exit area of 3.14 sq-in. A computer fan can probably not generate the pressure needed to create an exit velocity four times that of the inlet velocity (conservation of mass for incompressible flow) so you are probably not moving very much air. Recommend you enlarge your exit holes to 2-in-diam to match the input area of the fan.

 

[d_rock]

Why not try to layer a couple more layers of foam around the coffin to see what that will do to ur temps? I like ur setup.

I didn't add foam to the front of the coffin around the taps simply because of space. I bought the thicker foam and it would block airflow from the fan to the faucet shanks. There is foam on the back panel that comes off the coffin, and all joints are caulked. The fan is always on, so my layman's reasoning says that airflow is more important than temperature retention in the coffin itself.

@d_rock, the area of a circle is pi*D^2/4, so your 4-in-diam input fan has an inlet area of 12.57 sq-in, but your four 1-in-diam exit holes only have a combined exit area of 3.14 sq-in. A computer fan can probably not generate the pressure needed to create an exit velocity four times that of the inlet velocity (conservation of mass for incompressible flow) so you are probably not moving very much air. Recommend you enlarge your exit holes to 2-in-diam to match the input area of the fan.

I do appreciate your calculations on my behalf, but consider this:

The intake hole under the fan is slightly smaller than the diameter of the fan, say 3" (I can guarantee my jigsaw cut circle is not perfect ). So the inlet area of a 3" hole would be around 7 sq in. That measurement doesn't take into account the surface area of the fan/motor/chassis blocking airflow in, however. The fan motor itself (center of the fan blade assembly) is around 1" in diameter (.79sq in), not to mention the chassis braces that cross the fan opening, so with the motor and chassis we'll consider approximately 1sq in of area to block airflow- that would make the actual inlet area around 6sq in. The four 1" holes have approx. 3.14sq in inlet area.

You are right that my in/out balance is off, but after looking at it like this, it's less than 2x rather than 4x. I may add two more 1" holes, but it's all together now and I'm seeing about a 8-9 degree differential between the coffin and keezer. Seems like that's about the best that people are getting with separate coffin boxes, so I'm good with that. No issues with foaming and my taps are cold enough to condensate when I pour, but not so cold that they sweat at other times. I think it's a good balance.

I am considering rebuilding my lid/coffin altogether, to make sort of a collar/coffin combo. It would allow a keg on the hump, while still having a 6-8" lower ledge on the front of the lid for a drip tray and faucet overhang.

@DurtyDawg - Sorry to hijack your thread! Your keezer was one of the main examples that really got me set on the coffin keezer option. Great design.

 

[MusicalBrewer]

@MusicalBrewer - Here's my final setup. Nothing fancy at all, I put a 4" PC fan in the tower pulling up, and another 4" fan in the floor of the keezer (I used long screws as posts to keep it 2" off the floor). With just the coffin fan, it kept temps 10-12 deg higher than the freezer temp. I decided to add the second fan in the freezer floor and it seemed to help, it dropped the coffin temp by 2 degrees. Now I'm seeing just under a 10 degree differential between coffin/freezer on average. I'm using Perlick 650SS and 10' of beer line, so any foaming issue is pretty much negated by the equipment, but the cold lines are going to keep that beer in the line fresh.

I plan to make a new keg floor/PVC duct system eventually that will better circulate air in the keezer, and hopefully reduce some condensation issues I'm having.

Hey d-rock, thanks for the update. I'm surprised there is that much temperature differential. It looks like the coffin is fairly small.

There was another thread titled "keezer insulation" (sorry, don't know how to post a link). In it there was a recommendation to use Armaflex 1/2" foam sheet insulation. Apparently this type of insulation is far better at keeping the cold in. I haven't got any yet, but want to give it a try.

I had a pvc floor system in a previous keezer--it was awesome. I didn't put a collar on so I don't have room for it in my current one...otherwise I would do it again. I'll bet when you get that done it will bring the temperature differential down!

 

[DurtyDawg]

Check the R-value of the insulation. The higher the R-value means better insulation value. Ridged foam is usually better in tight applications. Make sure ur joints are caulked very good to stop air loss.

 

[jbb3]

And once you get all your rigid foam insulation installed, I found this stuff is great for sealing things up and adding a few more Rs.