Insulating beer chiller line

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

jcojr72

Well-Known Member
Joined
Mar 29, 2010
Messages
88
Reaction score
1
Location
Southern NH
I have attached a diagram of how I intend to cool my beer line that will run from the basement to the kitchen. The cold air will be blown from the fridge into the inner pipe (where the lines are running) and return via the larger outer pipe. My question is which PVC pipe should I be insulating, the large outer one, the inner one, or both? This will be running between 2 walls, which have about 9” of clear space. Also, what type of insulation do people use? All I can think of is the black foam insulation for pipes that I always see at Home Depot, but I cannot remember seeing it in diameters this large. Thanks for the help ahead of time.

 
Condensation is bound to appear even if it is insulated. The temp change will make lots of mold inside those walls.
 
Any reason you don't want to go with water/glycol cooling? It seems like it would actually be a lot more work to do the pipe within a pipe method than setup a pump and bucket.
 
The reason I was shying away from glycol/water cooling is only that I was more comfortable with fans than pumps. Does the glycol need to be in a freezer, or is having it in the same temperature as the beer sufficient? I will read more about glycol cooling, but a few questions I currently have are, what material is the glycol tubing loop (same tubing as beer line)? Does it need to wrap around the beer lines or simply run within the same insulation? What happens when I get up to the taps, does the glycol line just loop around and come back down inside the insulation? Does the line need to wrap around the shanks? Thanks for the help, I will read around about glycol cooling.
 
From what I've seen (which is not a lot) it seems the most common way is to have a bucket of glycol in the freezer and a pond pump, the lines run staight with the beer lines (i think it is just beer line they use for the glycol) at the end I have seen some that use a "U" of cooper tube in the faucet tower to loop back into the return hose that runs back down with the beer lines again finishing in the bucket.
I am probably wrong on something but you should look into it for sure, add benifit is the lines from the keezer to the taps will be more flexible and easier to deal with
 
Yeah, from what I am reading it seems that ideally the glycol is run from the freezer so that it is extra cold. Unfortunately I am converting a stand up freezer to a fridge for the kegs, and will not have a freezer. However it seems that some people have had luck with having the glycol reservoir in the fridge (could be water now because not below freezing). Can anyone chime in on whether my lines are too long for using a glycol system with the reservoir at refrigerator temperatures? The reservoir would likely be in the bottom of the fridge, but I could try and run the lines up through the top of the fridge to keep them in a chilled environment as long as possible. From the top of the fridge the lines would exit and run about 7' up to the taps in the kitchen. Has anyone had success with similar lengths and the reservoir in the fridge not a freezer.

Thanks.
 
My chiller is in the cooler, but my total run outside of the keezer is only about 7'
You can see the build, pump, and the copper loops here

So far the results are pretty promising. It did a good job of keeping the beer in the lines cold. Of course, nothing is 100% efficient, so I'm not expecting exact keezer temp in my trunk line. However, last weekend I did measure the temp of a few ounces of beer that sat in the trunk line for about 30 minutes, and it was only 1 degree warmer than the keezer! But, my system is still pretty green, and I have more real-world testing to do.

There are a few things I would recommend...
Don't use beer line for the glycol. The walls are very thick and therefore very inefficient at heat transfer. Also, the diameter would severely restrict your flow rate. If your trunk line won't be moving, I would use copper pipe in the trunk. Copper transfers heat far better than vinyl lines, and your cooling system will be more efficient. Unfortunately, I needed my trunk to be flexible so I could slide the keezer out from under the bar for loading/unloading. I used used 7/16" diameter, thin wall vinyl tube because it fits well with the 3/8" copper in my system. For the parts that don't have to move, I did use copper.

For the chiller, a lot of people here use an old corny for the reservoir, with a pond pump for circulation. From what I've read, they have had pretty good results. My system is a little more complicated for 2 reasons. The first is I don't have room in my keezer for a large tank of coolant. The second is because I thought having a smaller volume, actively cooled with a fan and heat exchanger would present more coolant to the cold keezer air. My total volume is about a pitcher full!

Keep us posted on your progress! I'd love to hear real world results from someone else trying this...
 
Thanks for the response sweetsounds. I read about you build, it is looking good. I think I have been swayed from air cooling to water cooled. I am going to stop at Home Depot tonight and get started on this.

For the pump, my cooling line will start from the fridge run up to the kitchen and back down. If I place the cooling reservoir on the floor of the fridge this would be about a 12' rise, if I put it on a shelf in the top of the fridge it will be about a 7' rise. At first I was thinking that I would need a pump that could handle the 7 or 12 foot head, however since this is a closed loop that is starting and stopping from the same reservoir I think that there is no net elevation head. Therefore the only resistance is due to the friction of the cooling line (about 20' worth. If this is true I would think the smallest pond pump I can find would work? Something like this http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053 Am I missing something here? Has anyone used a fountain pump like this http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053 The fountain pumps seem to be cheapest so it is worth a shot.

Thanks again
 
I think you're right about the net head pressure to the pump. It would stand to reason that the weight of the coolant you are pushing up will be offset by the weight falling back down the other side.

Most of the guys here are using pond pumps, but I'm not sure if the one you linked is the same/better/worse. And I have no experience with that pump.
I'm using a Maxi-Jet 1200 aquarium powerhead. It's submersible, but it's the only one I could find that was also rated to run outside of the tank (necessary in my build)
It's rated for 295gph with a max head of 5.75 feet. My entire system is about 22' of 7/16 vinyl, 3/8 copper, and 1/2 aluminum piping. It takes the Maxi-Jet about 15 seconds to pump through the circuit. So the flow rate is definitely not stellar. 22' at 7/16 diameter (guessing the average here) is 39.7 cubic inches of volume. It takes 15 seconds to take a lap, so 39.7 * 4 and converted to gallons is .68 GPM or about 40.8 GPH. I'm getting about 14% of the pumps rated volume in the real world. I think this works in my chiller because my total system volume is only around 1/2 gallon, counting the reservoir. So my coolant passes through the radiator and fan around 80 times every hour for active heat exchange. (As opposed to sitting in a pool/bucket/tank etc)
Your lines and your volume are about the same as mine. So without using a bigger pump, you will see a little less throughput, and heat transfer. But, your heat sinking efficiency will be higher than mine, too, if you use copper throughout.
I guess the worst that can happen is that pump isn't strong enough, and you have to return it, or eat the $20! A small price to pay IMO for the fun of engineering things like this :mug:
 
Sounds right about the net head, but just remember that you will need to prime the system if you pump wont handle the 12' or so, basically the net head thing is setting up a syphon so if there are any air bubles that could cause the syphone to stop. And remember that the rated flowrate is at 0 head and drops off quite quickly (and rate head is at 0 flowrate).
Also IIRC the benifit of glycol over water is that gycol's freezing point is below that of water, i.e. you can cool it down to under 0 deg C and get the benifit of a larger temp difference. If you are above the freezing point of water I think that water is actually better fluid for heat transfer (higher specific heat capacity), don't quote me but something to think about/investigate.
 
I was thinking about needing to prime the line to get the siphon started. I am hoping that once the system is running the siphon will not be broken or I will need to get a pump able to handle the full head. I am going to pick up the pump tonight and give this a shot, I will let you know how it goes.
 
I don't see any reasons for the siphon breaking really but thought I better put it out there. Let us know how it goes.
 
So I went to Home Depot tonight and bought this pump http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053 . I also bought 20' of 3/8" (OD) flexible copper line and 10' of 3/8" ID vinyl tubing. I wanted to test up to what head the pump could prime the line so I hooked the 10' of vinyl tubing to the pump outlet and all 20' of copper tubing to the end of the vinyl and placed the pump in a bucket of water. The specs for the pump say a max head of 7.3ft, but I found even with all the tubing connected that I could prime the line up to 8'-9". The good news is that this is approximately what my elevation change will be so I should be able to make this work without having to prime the line myself. In doing this I was also reminded at how good of a conductor copper is. The copper line became instantly cold when the water passed through, whereas the vinyl line never felt cold. In the final setup I plan on running the copper line from the pump outlet, up the insulated enclosure with the beer lines, wrap the copper around my 2 shanks, then start coming back down the line until I run out of the 20ft length, then I will splice on the vinyl tubing for the remainder of the run back to the reservoir. I figure having the copper at the beginning of the loop will benefit the most as the water is coldest here. I suppose running copper the full length of the line would be best, but I think this setup will suffice and would rather not buy another coil of copper.
 
Back
Top