PEX pipe for outer shell of counterflow chiller?

[bigljd]

I'm planning to build a DIY counterflow chiller and was pricing things out at Home Depot on the way home from work. My first thought was using 3/8" copper tubing for the inner, and a 1/2" copper outer shell, but copper is pretty pricey so I looked around and saw the PEX pipe. For $7.85 for 25' of 1/2"ID tubing, I believe it's cheaper than most garden hose, especially the rubber heat resistant type, and much cheaper than 1/2" copper.

Would it work to run 3/8" copper tubing thru the 1/2" PEX pipe?

I do plan to run boiling wort through the counterflow chiller with my pump for 5-10 minutes to sanitize the copper before turning on the water, so I'm pushing PEX's 200 degree rating by a few degrees. I also think PEX may be tougher to uncoil to push or pull the copper through, and tougher to coil it up very tightly after the copper is in, but that doesn't bother me to much if I have a larger diameter coil.

Google couldn't find me anyone else who has tried this - is there a reason why people aren't doing it?

This resilient SharkBite 1/2 in. x 25 ft. PEX Pipe can withstand a minimum working temperature of 32 degrees Fahrenheit and a maximum of 200 degrees Fahrenheit.

Strong, flexible cross-linked polyethylene construction
SharkBite imprint pattern provides a visual aid for easy assembly with SharkBite push-fit fittings (not included) without the use of costly tools
White color
Maximum working pressure of 160 psi
Minimum working temperature of 32 degrees Fahrenheit and a maximum working temperature of 200 degrees Fahrenheit
Compatible with SharkBite push-fit fittings or barbed fittings (not included)
For a wide range of residential and commercial plumbing applications including potable water systems

Actual inside diameter (in.) : 0.5
Actual outside diameter (in.) : 0.63
Assembled Depth (in.) : 29 in
Assembled Height (in.) : 29 in
Assembled Width (in.) : 6 in

 

[EFaden]

I'm planning to build a DIY counterflow chiller and was pricing things out at Home Depot on the way home from work. My first thought was using 3/8" copper tubing for the inner, and a 1/2" copper outer shell, but copper is pretty pricey so I looked around and saw the PEX pipe. For $7.85 for 25' of 1/2"ID tubing, I believe it's cheaper than most garden hose, especially the rubber heat resistant type, and much cheaper than 1/2" copper.

Would it work to run 3/8" copper tubing thru the 1/2" PEX pipe?

I do plan to run boiling wort through the counterflow chiller with my pump for 5-10 minutes to sanitize the copper before turning on the water, so I'm pushing PEX's 200 degree rating by a few degrees. I also think PEX may be tougher to uncoil to push or pull the copper through, and tougher to coil it up very tightly after the copper is in, but that doesn't bother me to much if I have a larger diameter coil.

Google couldn't find me anyone else who has tried this - is there a reason why people aren't doing it?

This resilient SharkBite 1/2 in. x 25 ft. PEX Pipe can withstand a minimum working temperature of 32 degrees Fahrenheit and a maximum of 200 degrees Fahrenheit.

Strong, flexible cross-linked polyethylene construction
SharkBite imprint pattern provides a visual aid for easy assembly with SharkBite push-fit fittings (not included) without the use of costly tools
White color
Maximum working pressure of 160 psi
Minimum working temperature of 32 degrees Fahrenheit and a maximum working temperature of 200 degrees Fahrenheit
Compatible with SharkBite push-fit fittings or barbed fittings (not included)
For a wide range of residential and commercial plumbing applications including potable water systems

Actual inside diameter (in.) : 0.5
Actual outside diameter (in.) : 0.63
Assembled Depth (in.) : 29 in
Assembled Height (in.) : 29 in
Assembled Width (in.) : 6 in

Seems like it would work. The problem I see is that it isn't really easy to bend and get into the correct spot. It just seems like it could be a bit annoying to build it, but I'm curious to see it.

 

[Ohio-Ed]

I use 1/2" PEX in place of a garden hose to provide fresh water to my brewing area on brew days.

PEX is not very flexible. I think it will be harder getting the copper through the PEX than a garden hose. I also think it will be a challenge to get the PEX in much of a smaller diameter coil than you buy it in.

 

[bigljd]

I guess I'll check it out again tomorrow at HD and play around with a coil of it and see if I think I can make it work. If not I'll probably just fork out the dough for copper and make something nice with it. Thanks!

 

[mabrungard]

PEX will be fine for a counterflow chiller. Its fine at boiling temperatures too as long as its not pressurized. Since I doubt you'll have the outer jacket pressurized while you're santizing, it will be OK.

You definitely do not want to use copper as the outer jacket since its expensive and its heat conducting capability doesn't do you much good in this case. I'm not sure that the 1/2" PEX will have a large enough ID to accomodate the 3/8" OD copper and get enough flow through there. Might have to bump up to 3/4" PEX.

With the help of 2 friends, it will be no problem to lay the PEX out relatively straight and slide the 3/8" copper inside and then wrap the assembly around a mandrill. Be sure you think through the end pieces for your chiller to transition from the PEX and seal the 3/8" in.

Go for it.

 

[Bobby_M]

The only advantage to an all copper CFC is the ability to oven sanitize like a plate chiller. If you don't feel that is necessary than PEX is fine. While it's rigid to work with, it has a slick surface compared to rubber hose and the copper should slide through easier as long as the leading edge of copper has a cap on it.

 

[BetterSense]

This sounds like a really good idea actually. Let us know what sizes and fittings you use and how you put it together.

 

[lazybean]

OP, With your concerns about the Heat from the boiling water and the PEX. The 200* is for it to maintain its pressure rating, your cfc should see minimal. Even when running the outer jacket will only see a few PSI from the outflow resistance.

 

[bigljd]

PEX will be fine for a counterflow chiller. Its fine at boiling temperatures too as long as its not pressurized. Since I doubt you'll have the outer jacket pressurized while you're santizing, it will be OK.

You definitely do not want to use copper as the outer jacket since its expensive and its heat conducting capability doesn't do you much good in this case. I'm not sure that the 1/2" PEX will have a large enough ID to accomodate the 3/8" OD copper and get enough flow through there. Might have to bump up to 3/4" PEX.

With the help of 2 friends, it will be no problem to lay the PEX out relatively straight and slide the 3/8" copper inside and then wrap the assembly around a mandrill. Be sure you think through the end pieces for your chiller to transition from the PEX and seal the 3/8" in.

Go for it.

I went to Lowes at lunch today to see what they had, and played around a bit more with PEX. I realized too that I'd have to go to 3/4" PEX or the copper would fill most of the inside of the PEX. And that 3/4" PEX is even stiffer and more of a PITA to coil. I wonder if it softens up if I put some hot water thru it before trying to coil it?
I think the toughest part is to figure out how to seal in the 3/8" copper. I only had 30 minutes to kill today and didn't see any solutions, but maybe if I had more time I may be able to figure something out.
I added up the cost for an all copper CFC and I think I'd have at least $110 in it just for copper and connectors. I think I'd rather just spend the extra $75 and order the one pre-made from Morebeer.
I haven't given up on PEX yet, I just need to go stare at stuff in the plumbing section for a while and see what I can come up with.

Thanks!

 

[Spintab]

...I just need to go stare at stuff in the plumbing section for a while and see what I can come up with.

I love staring at stuff in the plumbing section. So many nifty things to build from all that stuff. I can usually coerce my 6 year old son into joining me too so he can put all the fittings together like legos.

I would definitely try running some hot water through the PEX to see if it softens up. It might work. I'm really curious how it all works out. Please keep us updated.

 

[Spintab]

Wait...why couldn't you just make the CFC a large diameter like 18-24"? That's what, 4 1/2 to 6 feet per revolution. Make maybe 4 revolutions. Depending on how your kettle is mounted you could kinda wrap it around the kettle as you're draining.

Just a thought

 

[Ohio-Ed]

I went to Lowes at lunch today to see what they had, and played around a bit more with PEX. I realized too that I'd have to go to 3/4" PEX or the copper would fill most of the inside of the PEX. And that 3/4" PEX is even stiffer and more of a PITA to coil. I wonder if it softens up if I put some hot water thru it before trying to coil it?
I think the toughest part is to figure out how to seal in the 3/8" copper. I only had 30 minutes to kill today and didn't see any solutions, but maybe if I had more time I may be able to figure something out.
I added up the cost for an all copper CFC and I think I'd have at least $110 in it just for copper and connectors. I think I'd rather just spend the extra $75 and order the one pre-made from Morebeer.
I haven't given up on PEX yet, I just need to go stare at stuff in the plumbing section for a while and see what I can come up with.

Thanks!

PEX has a memory and tends to go back to the shape it was extruded in. If you kink it, you can heat it with a heat gun and it will go back to the original round shape. I have a 100' coil that I put garden hose fittings on and use for brewing instead of a garden hose. I have used it for over a year, including laying out all day in the summer sun, and it still goes back to about the same shape as when I bought it.

 

[joeybeer]

Why not use a garden hose for the outer jacket?
Using copper for the outside jacket just seems like a waste of $, the cooling water is never near the beer.

 

[Lucky_Chicken]

I love staring at stuff in the plumbing section. So many nifty things to build from all that stuff. I can usually coerce my 6 year old son into joining me too so he can put all the fittings together like legos.

this should definitely be in the "you might be addicted to homebrew if" thread... made me laugh

I like the copper outer because you can bake it to sterilize. That said I use a hybrid chiller, that the otter jacket is made out of plastic.

 

[Diver165]

I'm like the rest, this will be interesting to see.

I've used PEX in my home when I did an extreme remodel/expansion. It's awesome! But like the others have said, it doesn't like to bend in tight places. I have my main PEX manifold fed by a 3/4 PEX line. I can vouch it doesn't like to bend in tight places. Those poor plumbers...lol Seeing them wrestle that 3/4" PEX line into the maniforld w/o kinking it. Scenes of a monkey doing unspeakable things to a football came to mind. LOL

 

[bigljd]

Well I wasted another 1.5 hours after work tonight staring at plumbing parts, but I think I have 2 possible solutions, and I picked up parts, PEX and copper coil to try it.

The cheap and maybe easy way is to cement a 90 CPVC elbow to the ends of the PEX (a 3/4" elbow fits on pretty snug on the 3/4" PEX). The elbow would have a hole drilled straight into it large enough to let the 3/8" copper pass thru it snugly while sticking out of the elbow about 2- 3". I'd seal the copper tube/cpvc elbow hole with some JB weld or silicone, and then cement on some hose connects to the other end of the elbow. Not sure how secure this would be, but if it fails I'm only out about a dollar for the elbows.

The other method involves cementing a CPVC T to the PEX, and then gluing that to a CPVC/brass union that I can solder copper to. Then I'd just use Bobby's CFC Wiki method of copper reducers to seal off the 3/8" copper, and cement hose connects to the other opening on the T.

I probably won't have time to attempt this until the weekend, but I'll try to take pictures (unless it's an epic fail). I think one of the two options should work, I hope.

As far as coiling the PEX, I think I may go for a larger ~18" coil (about the same size as it come from in the store) and just coil it around the legs of my kettle stand. Some zip ties could hold it together, and a couple of bolts or nails in the stand legs could keep it from sliding down to the floor.
Here's my kettle stand.

 

[bigljd]

Why not use a garden hose for the outer jacket?
Using copper for the outside jacket just seems like a waste of $, the cooling water is never near the beer.

I want something that will last - if I'm pumping boiling hot wort through it for 10 minutes to sterilize it before turning on the water, I don't think garden hose will last except maybe rubber hose, and that is a bit pricey. Using copper as the outer shell is super durable, but also super expensive.
I'm hoping PEX will give me durability at a cheap price. Plus I don't think it's been tried so there's the 'trying something different' aspect of it.

BTW (not related to joeybeer's post) the 3/4" PEX was around $13 for 25', so it's a little more than the $7 for the 1/2" I mentioned in the original post. I'm using 3/8" ID copper tube in the 3/4" PEX. I like the larger inside diameter copper - I think there will be less chance of me plugging it up with hops or trub, but it did cost me about $41 for 20'.

 

[kklowell]

My bet is that it will work well.

 

[edecambra]

Subscribed!

 

[Spintab]

So this is off topic but I see an electrical box on the side of the kettle so I'm assuming you have a heater element in there? How is the element attached? I'm planning on doing the same on a kettle I'm waiting on. Considering doing it myself and soldering a half coupling into place to screw an element into. That way I could pull it out if I need to use a burner for whatever reason.

 

[Dert]

You're nuts if you want to attach anything to PEX with JB weld or silicone. Use proper fittings to go to copper and just do it.

I've run >5000' of PEX in my house and garage...

Yes it's ridged, but if you heat it up and have copper in the center, there is no reason it won't work. Transition form PEX to copper...

 

[joeybeer]

Spintab- you're opening up quite a can of worms ! Look out ! Check out the Electric Brewing Forum

I just had a quick look in there, and now I sit up all night staring at wiring diagrams and looking through switch catalogs I didn't know existed 2 weeks ago

 

[bigljd]

You're nuts if you want to attach anything to PEX with JB weld or silicone. Use proper fittings to go to copper and just do it.

I've run >5000' of PEX in my house and garage...

Yes it's ridged, but if you heat it up and have copper in the center, there is no reason it won't work. Transition form PEX to copper...

I'm not attaching anything with JB weld or silicone. The plan would be to drill the hole at the right diameter thru the elbow so that I have to force the copper tube thru the hole. The only thing the JB or silicone would do it to fill in any tiny gaps and seal off the connection. Keep in mind that there is minimal to zero pressure in counterflow - if I drilled the holes correctly I might not need anything to seal it. The JB or silicone would eliminate any possible leaks.

I have parts to do it with proper fittings too, but I want to try this low budget method first to see if it works. My only concern is drilling a clean hole, since I don't have a drill press and the 2 drills I have are both wobbly and out of balance.

 

[bigljd]

So this is off topic but I see an electrical box on the side of the kettle so I'm assuming you have a heater element in there? How is the element attached? I'm planning on doing the same on a kettle I'm waiting on. Considering doing it myself and soldering a half coupling into place to screw an element into. That way I could pull it out if I need to use a burner for whatever reason.

Here's my build thread if you want to check it out. My element would be fairly easy to replace too, if I needed to. It's weldless/solderless.


https://www.homebrewtalk.com/f170/my-two-5500-watt-element-1-pid-ssr-build-281085/

I copied Kal's method from electricbrewery.com, but used single gang boxes and used the nut and o-ring from Bargain Fittings to seal everything from the inside. The Pol has a different way of doing it too, if you search HBT for his thread.
Soldering or welding connections to your kettle would work too. Others have done that, and I know there are some threads in here on soldering fittings.

 

[Spintab]

Here's my build thread if you want to check it out. My element would be fairly easy to replace too, if I needed to. It's weldless/solderless.


https://www.homebrewtalk.com/f170/my-two-5500-watt-element-1-pid-ssr-build-281085/

I copied Kal's method from electricbrewery.com, but used single gang boxes and used the nut and o-ring from Bargain Fittings to seal everything from the inside. The Pol has a different way of doing it too, if you search HBT for his thread.
Soldering or welding connections to your kettle would work too. Others have done that, and I know there are some threads in here on soldering fittings.

Cool, thanks for the link. I was looking at that nut and o-ring and that would be the easiest way. I really want to be able to reliably take it in and out each time I brew to clean the kettle though, hence the thought of soldering. I'll probably rig up some 555 circuit for regulating the boil or just use the arduino I use for my hlt. We'll see. I don't have all the pumps and everything so I'm not looking to automate everything, just looking to cut the propane cord.

K back to the CFC

 

[Bobby_M]

There will be a bit of backpressure in the coolant side of things especially if you hook up a garden hose to the output. I don't know if a press fit through a drilled holeis going to work.

If you took my design using a 1/2" copper tee with a 1/2 x 1/4" reducer on one end, I think the PEX could just get clamped to the other end of the tee. 3/4" pex has an ID of .671" so that's pretty darn close to the OD of a 1/2" copper fitting.

 

[bigljd]

There will be a bit of backpressure in the coolant side of things especially if you hook up a garden hose to the output. I don't know if a press fit through a drilled holeis going to work.

If you took my design using a 1/2" copper tee with a 1/2 x 1/4" reducer on one end, I think the PEX could just get clamped to the other end of the tee. 3/4" pex has an ID of .671" so that's pretty darn close to the OD of a 1/2" copper fitting.

I do plan to attach a short hose (6ft) to the output, but will not restrict the output with a valve or anything so I don't think the pressure will be enough to cause any problems. I've been wrong before though, so we'll see what happens. I did pick up a cheap Harbor Freight drill press on sale for $69 today. I wish I'd have bought it before building my electric rig - it would have made things a lot easier. I just got tired of thinking 'man, I wish I had a drill press' every time I start a project.

I've got some 1/2" copper fittings lying around in the shed so maybe I'll play around with them a little first before trying the elbow method. I think I tried jamming a 1/2" tee into the PEX at Lowes and couldn't get it to fit, but maybe softening the PEX in some boiling water or something might make a difference. That may be an option too, I think.

 

[leggettg]

One year after the thread was started I decided to build a counterflow chiller out of 3/4 PEX and 3/8 copper. I only bought a 20' section of copper but now that it is built I think I will extend it with another 20' or 30' piece. I was not able to get the right fittings to go from PEX to a garden hose so I used to spigots and I will need to adapt one of them for the inlet.

I had to drill the 3/4 X 3/4 X 1/2 PEX T fitting so the copper would fit inside but after that it was easy to flux and solder the pieces together. I will try it out this weekend to see how cool I can get boiling water, luckily my well water is below 60 so it might work out well as-is.

 

[bigljd]

Nice job. I have to admit that my attempt failed - it leaked and I got pissed off at it and pulled the copper out to use it for something else. Looks like you did a much better job at it than me. What are the bands going around the pex? Looks like they do a better job at preventing leaks than what i did (don't even remember what I did). Since my plan sucked, maybe you can elaborate on your build so others can copy it.

 

[ThreeDogsNE]

I gotta say that I made a CFC with a garden hose using 3/8 o.d. copper tubing, and chilling 10 gallon batches with it was a major time commitment. I replaced it with a plate chiller, with 1/2 inch tubing connections. That cuts a chunk of time out of the brew day. At the prices for copper these days, I would tally up the cost of the copper tubing, the rubber hose, and all the other fittings and compare that against something like these: http://www.dudadiesel.com/search.php?query=+beer++wort++chiller&i=beerchillers On these, the tubing slides on, the hoses twist on, and you are in business. You supply the tubing and hose clamps for the wort, and the garden hoses that deliver and carry away the cooling water, just as you will with a CFC, but that's it. Oh, yes, and you can sterilize it in the oven, as mentioned above. I wish I had just started with one of these.

 

[leggettg]

Looking back I could have saved money on a 30 plate chiller. My thought was to save money because I already had the 3/4 pex but now I am going to add another 30' of copper and a couple more fittings and that will put me right under $100 for the chiller.

The copper bands are the rings that compress and seal the PEX. This is the same thing I would use if I was going to run a water line in a house. The only difference is the PEX has a 3/8 copper water line running inside of it.

Now that I have it I will continue to use it, I guess home grown is not always cheaper, but it was still fun to build!