Soldering a HERMS coil

[Markd27]

I recently ordered a HERMS coil for my HLT, but after receiving it and the seemingly overly expensive fittings, it’s going to be a very tight fit. The fittings are much longer than I expected, and frankly, appear to be at least 1/2” to 3/4” longer than they need to be on the compression side.

The main issue is that where the bends are placed in the coil, the tubing is quite a bit out of round, so the ferrules barely fit and won’t slide very far onto the tubing, pushing the coil out even further than what you see in the second pic below.

All that to say, does anyone see an issue with simply soldering in the tubing to the compression fitting end and not even messing with the compression ferrules and nut (third pic below)? I can’t see a need to routinely have to remove the coil, and even if I did, I could simply remove the outside nut on the fitting or simply desolder it.

I figured I would ask since I could not find another example of someone doing this, and it seems to make more sense in my mind than messing with the compression fitting and possible leaks, etc. I just wonder if the solder joint will be strong enough to support the weight of the coil without cracking or weakening down the road.

 

[day_trippr]

There can be considerable stress on the tubing to fitting connection with the weight of the coil hanging out in space. I'd be leery of a soldered solution if only because if it ever leaks it'll be that much more of a pita to remove, resolder, reinstall, etc.

fwiw, I went with a much shorter bulkhead compression fitting to mount my 50' 1/2"d hex.
A bit pricey indeed, but it was easy enough to install and has never leaked after a few hundred gallons worth of brewing...

Cheers!

 

[Hopsimus]

fwiw, I went with a much shorter bulkhead compression fitting to mount my 50' 1/2"d hex.

Another plus to the connectors from brewhardware is that they are bore thru.
That means you can push the tube as far as you want thru the bulkhead.
So, not only are they shorter than other brands, but the tube will slide in more. Those two things combined should allow you to easily fit your coil in.
(They also have a 3/8" version, can't really tell from your picture how thick your coil tubing is).

I've never done stainless welding, so can't give an opinion there.

 

[Markd27]

There can be considerable stress on the tubing to fitting connection with the weight of the coil hanging out in space. I'd be leery of a soldered solution if only because if it ever leaks it'll be that much more of a pita to remove, resolder, reinstall, etc.

fwiw, I went with a much shorter bulkhead compression fitting to mount my 50' 1/2"d hex.
A bit pricey indeed, but it was easy enough to install and has never leaked after a few hundred gallons worth of brewing...

Cheers!

Yep, the weight stress was what had me concerned. The fittings I ordered were actually more expensive than those ($27/ea, which seems insane for a small bulkhead), and I had considered both prior to ordering. I went with these due to them being one piece construction.

Do you happen to have the overall length of the ones you have, and the length on the inside and outside of the mounting point (kettle wall). I don’t see those specs on the Brew Hardware site. Thanks.

 

[Markd27]

Another plus to the connectors from brewhardware is that they are bore thru.
That means you can push the tube as far as you want thru the bulkhead.
So, not only are they shorter than other brands, but the tube will slide in more. Those two things combined should allow you to easily fit your coil in.
(They also have a 3/8" version, can't really tell from your picture how thick your coil tubing is).

I've never done stainless welding, so can't give an opinion there.

That’s a great point, the problem is that my coil has bends that take the tubing out of round near the mount point, so the tubing will not slide very far into the fitting. I could try to shape it back to normal, but risk knicking the surface which might create leaks.

If you look at the pic below, that is as far as the ferrule will slide on. I suppose I could use nylon ferrules which will form to the tubing, but too far out of round will cause leaks I would think.

 

[day_trippr]

[...]Do you happen to have the overall length of the ones you have, and the length on the inside and outside of the mounting point (kettle wall).[...]

Overall mounted length including the effect of the inside bulkhead silicone O-ring is 2-1/8".
That's from the outside face of the flare nut to the end of the threads.
The inside reach is 1-1/8", again including the silicone o-ring.

I used nylon ferrules on my hex with zero issues to date. Compressed inside the flare fittings I don't think there's a lot that can go wrong with them...

Cheers!