3 way parallel herms coil - reviews?

Hi All, just wondering if anyone has any real world experience with the fancy high flow herms coil?
I’m considering upgrading from my 15m coil in my 76 litre HLT, but would like to hear what others have to say about it when in real use.

I’ve read the experimentation results and it makes sense, but these don’t always translate to tangible real world results.

So questions;

  • Have you upgraded from another coil - if so what did you have before?
  • Did you achieve measurably better ramp times in your MTL as a result
  • Did it affect the variance between HLT and MLT, if you had one?
  • Do you run your HLT higher than MLT set temp?
  • What size is your MLT and HLT?

Currently the only reason I have my HLT set higher than my MLT is because there is ~ 1.5c variance when settled. If there was no variance, I would run my HLT at mash temp. No chance of overheating that way, even when flowing through the coil. Much more consistent and controllable results.


Yes I am using the new coil. Did an upgrade from the previouse 40cm. My current setup is 75L SS Brewtech as HLT, 75L SS Brewtech Mash infusion as MLT, and a 113L SS Brewtech for the BK.

My previous coil where the 40cm from brewpi, who also worked ok.
My ramp time where improved (5,5kW element) Previously it took about 25 min to ramp from 65c - 77c, this is now done in 13 min - with no overshooting at all.
Variance between HLT and MLT is minimal, Coil out (top one) is the MLT sensor in my setup. HLT is aprox 0,6c above the set-temp for this coil. This gives me nice and steady temperature inside my MLT. My variation is in the smallest digits ( 65c as set-temp, my temp is 64.95-65.04 inside the MLT

This is my best buy so far. I am extremly happy with the way it performs.

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Thanks Stig,

Wow, you halved your ramp times - that’s impressive!

I’ve not measured my ramp time during mash out but I’d guess it’s also around the 25 minute mark - possibly slightly more.
my pumps are a bit underpowered as well, so I think if I replace the pumps and the coil I should see a huge improvement.

$380 AUD shipped is still a very pricey herms coil. Just need to convince the boss.


Any pictures of your setup?

I think it is in the FOSBS Facebook group Thomas, if not, I can send you some.

Ill do Some testing soon. I have the discontinued long version atm. Once my new control panel is ready, then ill test both.

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