New Herms heat exchanger

So I am building my herms rig, and wanted a seperate heat exchanger from my HLT. I picked up a coffee urn from the thrift store for 2 bucks, and grabbed a big stainless pot for 6 bucks. I got my buddy to pick up 15 ft of 3/8" tubing for the coil. I am using a 110v 1500 watt element with a renco to control temps. I instafoamed it so it should be nice and insulated. For the lid I mocked up a wood lid, that I may just keep, added an 18volt drill battery with a stir rod JB welded on. I have a AC/DC converter to run it. Its setup to go, just have to wire it in.

thats pretty ingenious SSRider

I have been thinking of putting together a DIY flashboiler and like allot of the ideas you have there.
Keep us updated on your progress

Cheers
Steve

that's some mad-scientist stuff! have you used it yet?

not yet, Im welding(well soldering) all my fittings in the HLT,MLT, and BK tomorrow. Then I will start plumbing everything in. I need just little things to complete my single tier setup and I hope to brew a batch by next weekend.

My idea with this was that I could change mash temps much quicker with only about 1.25 gallons needing to be heated, vs having to heat the entire HLT. I should be able to do step-ups in just minutes. Im going to recirc the wort constantly and let the renco control the HX. I hope it works as well as I think it should.

I think the trick might be a balance between small volumes for quick control, but large enough for it to not swing too much. I bet if you do a continuous re-circ, it'll even out pretty easily, though.

I was once worried about step mashing in my HLT HERMS... but then I realized something... I dont have to be.

I strike at 130F to rest at 122F.

Meaning I initially heat my HLT to 145 or so, so that my strike water pre-heats my MLT.

After I strike and begin the rest at 122F, I turn up my HLT to 156F or whatever I want my next step to be.

While doing this, and resting at 122F, I am not recirculating for that 20 minute period.

When the 122F rest is complete, I start to recirc through the HLT HERMS, no lag time, because the HLT is already heated, it heats during the first step which takes 20 minutes anyway.

I have nearly 8 gallons of thermal mass in the HLT, so the element will not have to work too much when I begin the recirc.

I doubt that I will actually do step mashes very often, but since I am using a 1500w 110 element for my HLT, I didnt want to have to change temps in it too often. I want to heat it to strike temps, then up to sparge temps, while im mashing. Once I get my 240 setup rolling, I can use a larger element and it wouldnt be such a concern, but since I will already have the HX, I dont see a need to change it. Plus its kind of a cool piece of equipment.