About to mount elements, two questions

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tre9er

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Two things that I haven't seen a "this is the best way to do this" regarding mounting heating elements to a kettle. Granted this is a pot, not a keg.

1. What configuration of o-rings (stock and bargainfittings) is the best? I've seen people say to use stock on outside and just the 1" lock nut on the inside, without orange o-ring inside...and I've also seen people saying ditch the stock one and use bargainfittings stuff both on inside, nothing on outside...then I've seen people say it leaks either way.

2. Ground to the heater element flange itself or the pot itself? I want the safest way...unless they're the same.
 
There is a lot of good information on the Electric Brewery website, but I have to admit that I don't like the method used to seal the element penetration for the pots. I don't agree that the exterior washer and o-ring are needed or can be installed in some cases. When the metal thickness of the pot or keg is kind of high, there may not be enough threads on the element to allow that exterior washer and o-ring. There is a way to get around that.

First, I do like the junction box idea that Kal presents on his web site. Its very easy to construct and produces a safe enclosure. I have found that you do not need to use a double gang box. A single gang, aluminum box is roomy enough. The stainless plate epoxied to the box leaves you with a minimal thickness added between the element base and the lock nut you need to install inside the pot.

My philosophy is to keep all the liquid inside the pot and don't rely on an external o-ring to keep leaks from occuring. I like the 1" NPS nut and the 1.25" ID by 1/8" thickness o-ring on the interior of the pot. Leaving out all of the o-rings or gaskets on the exterior of the pot leaves you with more threads to seat the lock nut.

Obviously, the o-ring on the interior seals the interface between the pot and the lock nut. But this leaves the element threads as an unsealed area where liquid will exit the pot. It turns out that this is a perfect place to use silicone seal. I recommend that the threads on the element, lock nut, and the o-ring be lightly coated with silicone seal and then assembled. This is also a good time to apply a light coat of seal on the end of the element where its exposed to the wort. That area will rust in time.

Since you don't place any insulators between the junction box and the pot, the stainless plate will be in intimate contact with the pot. Since I used JB Weld to glue on the stainless plate to the J box, it has very low resistance between the ground lug in the box and the plate. Upon assembly, a check with my meter shows that the resistance between the ground lug and the pot was very low. Now I've got a secure ground for my pot. I feel this is a critical difference for this installation method. No insulators between the grounding lug and the pot means that my life is a little more safe guarded. Of course, you would need to check the resistance of that connection on an occassional basis. Brewing is not worth dying for. Having a good ground helps insure that the GFI will have the opportunity to protect you.

Enjoy!
 
So single gang metal boxes on the outside, lose the stock o-ring, use silicone on the threads of everything and use silicone o-ring and locknut on inside of kettle. Use stainless face-plate between j-box and kettle, jb-weld around that to keep it water-right. Don't pot or cover connections inside of j-box. Use stainless face-plate on outside of j-box too and jb-weld around that. Ground to j-box.

Right?
 
the problem with glue / silicone / epoxy is that they harbor bacteria and you can not disassemble them for cleaning or to replace the element. if you are stuck using weldless fittings, O-rings are really the only semi-sanitary way to do it. and you want the o-rings between the element and kettle wall in such a way that the element threads arent exposed to wort (if possible). threads are even worse at harboring bacteria.

now if you dont care about infections and figure that its going to be boiled anyway... be my guest and just JB weld the element perminantly into the pot.

also- if its for a HERMS system and the element isnt going to touch wort, then you dont have to be nearly as careful.
 
My thinking now is to do the following:

Use either the BF silicone o-ring or my baby-bottle nipple (silicone) method on the inside in conjunction with the SS locknut. Then coat the threads with PTFE tape to prevent water from traveling. This would allow me to disassemble and clean after each brew if I desire...or if I have an issue with the element I can easily swap it out.

On the outside I'm leaning towards a gang box for the same reasons: no potting of connections and can change out elements more easily if needed.

My issue is that I feel like there's probably not a truly watertight method of using a gang box that isn't permanent. The strain relief connectors aren't creating a waterproof seal where the cord exits the box. I suppose I could use silicone sealer on the box since it's not technically "permanent" although it's not fun to scrape out. Gang boxes are cheap enough though that replacing that is better than replacing the cord and everything else in the event the element fails (if it were potted).
 
the problem with glue / silicone / epoxy is that they harbor bacteria and you can not disassemble them for cleaning or to replace the element. if you are stuck using weldless fittings, O-rings are really the only semi-sanitary way to do it. and you want the o-rings between the element and kettle wall in such a way that the element threads arent exposed to wort (if possible). threads are even worse at harboring bacteria.

now if you dont care about infections and figure that its going to be boiled anyway... be my guest and just JB weld the element perminantly into the pot.

also- if its for a HERMS system and the element isnt going to touch wort, then you dont have to be nearly as careful.

Um, these things are getting heated to fairly high temperatures and being held at those temps for long periods. That is more than enough to provide acceptable kill performance for any evil critters! There is no cleaning needed or required. Ever.

In case my original post was unclear, the stainless plate is epoxied to the J-box. The box and plate assembly are held in place by the element and the lock nut. The silicone seal on the threads comes right off and does not lock the nut on. There is no problem with disassembly. Everything comes apart and can be cleaned. There is no need to disassemble though.

I hope no one is so highly intelligent that they would JB Weld an element into their pot. That would just be too smart for me. I don't think I'd want JB Weld for any epoxy in contact with my wort.
 
At this point I'm more concerned about the connections being water-tight, but I have to admit I don't like the idea of scrapping an element if I have an issue due to it being potted in jb-weld.

I may go to Menards and see if they have some sort of gang box that doesn't have umpteen holes in it, or slits, slots, etc. Something I can make into a water-resistant box for the connections, as you suggested. Yesterday when I was there it seemed like everything had tons of knockouts and/or slots cut in it, making it less than water-tight.
 
I picked up my aluminum J-boxes at Menards. They have the cheaper single gang box, but as you mention, there are too many holes. I had to buy the more expensive version (like $6 ea) in order to get boxes with 3 holes (one on each long end face and one in the bottom of the box). Since you're going to cut a hole in the bottom of the box, that hole doesn't matter. You do need to make sure that you get boxes with the larger holes in order to fit the power cord and wire grip. I think it was 3/4" vs. 1/2" Your power cord comes out one hole and the other hole is capped with a threaded insert that comes with the box.

Lowes has the fancy wire grips that come in various sizes to fit differing power cord diameters. Menards did not carry those items at my local store.

By the way, you don't need a hole saw for metal if you use aluminum J-boxes. A regular hole saw for wood will work very well. The aluminum didn't dull my hole saw. Since there is a hole in the bottom of the box, you will need to create a guide template to keep the saw from wandering. Take a piece of 1 by 4 board (or similar) and use the hole saw to cut a hole in the board. Then clamp that board to the back of the box (or hold it very tightly) and that will keep the saw from wandering.

Be sure to use the JB Weld to glue on the stainless plate. You have to prepare both the plate and the box for proper adhesion. Rub the back of the box on a sheet of sandpaper until the metal is fully exposed and paint removed. For the stainless plate, I suggest that you press the plate flat in a vise. You may have to pound it with a hammer to flatten it the last bit. The plate is bigger than the back of the box. If you want the plate to be sized to the box, you need to mark it and grind or cut it to size before you glue it on. It will break loose if you try to do that cutting or grinding after the fact. YOu will also have to rub the plate on the sandpaper as was done for the box. This removes the oils and coating on the plate. Be sure that all areas of the plate are roughed up for best adhesion.

Then glue it onto the box. I suggest punching the hole in the plate for the element prior to glueing. The Harbor Freight punch set is about $25 and works very well. No need to buy the Greenlee stuff unless you are a professional electrician and will be using it for a long time.
 
Got started last night. Ended up going a different direction. Man those hole saws walk a lot, too. Good thing the holes come out slightly undersized.

I cut holes in plywood so the elements would sit nicely while the jb-weld cures. I used PVC couplers with the weather-resitant covers and just jb-welded the elements around the edges but am not planning on potting the connections. This way I can replace wiring, etc. without having to chuck the whole assembly. If I do have to replace an element I will buy a new PVC housing at $2 each. Have some strain reliefs that fit into the bottom opening but have to use a rubber grommet as they don't crank down tight enough for my cord. Just got the grommet this AM so will see tonight if it helps.
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You can see the walking the hole saw did. I'd recommend a step-bit, even for aluminum, unless you have a nice drill-press that can keep the hole saw steady.

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My Camco 1500w foldback lime-life incoloy elements. They fit in the palm of your hand, ULWD.

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Got started last night. Ended up going a different direction. Man those hole saws walk a lot, too. Good thing the holes come out slightly undersized.

I cut holes in plywood so the elements would sit nicely while the jb-weld cures. I used PVC couplers with the weather-resitant covers and just jb-welded the elements around the edges but am not planning on potting the connections. This way I can replace wiring, etc. without having to chuck the whole assembly. If I do have to replace an element I will buy a new PVC housing at $2 each. Have some strain reliefs that fit into the bottom opening but have to use a rubber grommet as they don't crank down tight enough for my cord. Just got the grommet this AM so will see tonight if it helps.
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View attachment 50554

You can see the walking the hole saw did. I'd recommend a step-bit, even for aluminum, unless you have a nice drill-press that can keep the hole saw steady.

View attachment 50555


My Camco 1500w foldback lime-life incoloy elements. They fit in the palm of your hand, ULWD.

View attachment 50552

That is exactly how I mounted mine. I just used some silicone caulk around the outside of the element to fix a couple leaking issues.
 
I removed the "tube" part of the fitting because I didn't want the fitting sticking out 6" from the kettle. Just hack-sawed it off to make a more flush mount. I'm going to use the stock gasket and throw some silicone around it/the threads and then leak test it. I have a 1" SS locknut from BF.

The elements will be wired with male prong cords. These will plug into 15A switched outlets, both in a gang box that has male prong cords (short) coming out that will plug into my extension cords, which come each from it's own 20A GFCI outlet that's on it's own circuit.

I'll just switch both elements on to boil and switch one off if needed as boil get's rapid.
 
Here's the method I used. Dimpled and silver soldered a 1" half coupler in to a stainless blank cover. The dimpled and soldered the coupler/plate to the kettle wall. Wrapped teflon and used the element gasket against the coupler. Attached weatherproof box backwards with nuts and gasketed washers. Also used a hand-cut DIY gasket between plate and box. 3 day leak test produced nothing. Although it took two hours per element, I am happy with the finish. .3 ohms from my ground lug to the top of my kettle rim. Here are some pics:

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Of course some will argue that if my element gasket fails the water will collect in the box. All I can say is, heater elements and their gaskets are used continuously for decades without fail. I'm using mine a couple times a month. :)
 
Almost done with wiring the switch box. Mounted elements using bargain fittings o-ring because I had more leaks the other way I tried. Added silicone around hole before mounting due to sloppy hole produced by hole saw. Grounded to kettle. Doing initial water test now with two gallons. Will ramp up checking for leaks, then do a boil.

Pictures soon
 
No leaks with 6.5 gallons cold water after an hour. Started boil test with 6.5g of water at 50°.

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Just hit 70° after 8 minutes. 20° increase over that time.
 
25M and we are at 120°. 70° increase over that time.

Now 40m and at 160°, almost strike temp for a ten gallon batch (6.5g water in kettle now). 110° increase in 40m.

Now near sparge temp for a ten gallon batch at 175°. Clock is at 48m.
 
My thermometer doesn't quite agree, but I call that a boil. 70 minutes with 6.5 gallons from 50 to boil. 25 from sparge to boil.

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One element won't hold a rapid boil of this much volume in it's own. I tried. Maybe when it boils down some it would. I will see when I brew.
 

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