External HEX Vs. Internal

Is there a benefit to having your HEX say in a 2g cooler instead of right in the HLT? I'm in the process of building my HERMS and see some have external HEXs and some all in one. I have a cooler I can use so.. I need some direction.

Thanks!

My HEX is a 1500 watt element in a 2 gallon cooler. It works fine for me.

The reason that I didn't put my HEX in my HLT is because I wanted it to be as modular as possible. I sometimes BiaB or no sparge brew, so I don't need an HLT for those. Heating up the HLT to use the HEX would be a waste in those situations.

Although I do not have a HERMS at the moment, i have giving it some thought. My HLT will already have a heating element and thermometer. Using a cooler would require more space and extra equipment.

However using a smaller vessel like a 2 gallon cooler would allow quicker use of the Hex and more efficient use of heat. It is kind of a toss up.

I saw an article or post a while back where the brewer had made his HEX inside a 5 or 6 inch piece of pipe, with the rubbing inside, wrapped around an electric element, with water in that. Wish I could find the link, but really stays in line with the modular idea, and takes up much less space than a cooler. You can even mount it vertically on the mash tun for a nice autonomous unit.

So, it's hard to type on a phone. Rubbing = tubing.

A small standalone HEX can change temperature a lot faster than a HEX in a large HLT.
This can be a case of diminishing returns, as it still takes a while for the temperature change to propagate through the entire mash via recirculation.
It also decouples your sparge water from the mash; you can heat just your strike water and get the mash rolling, then heat your sparge water at your leisure.
It's arguable how much time/effort this may save.

Personally, I do use a standalone 2-gallon HERMS. I wouldn't necessarily rule out going to a HLT-based HERMS at some point in the future though.

Ok, I also have a corny keg that is no longer staying pressureized. I can use that as a HEX chamber as well. However if there really isn't a huge benefit, I can just put everything right into my HLT.

CoalCracker said:

Is there a benefit to having your HEX say in a 2g cooler instead of right in the HLT? I'm in the process of building my HERMS and see some have external HEXs and some all in one. I have a cooler I can use so.. I need some direction.

Thanks!

Click to expand...

Basically what you are looking at is a RIMS. A RIMS brewery uses an external HEX to recirculate and keep the Mash at a constant temperature. A RIMS uses a tube with an electric heating element that is controlled with a PID to recirculate the mash and keep the mash at a constant temperature.

https://www.homebrewtalk.com/f51/rims-dummies-114997/

Sawdustguy said:

Basically what you are looking at is a RIMS. A RIMS brewery uses an external HEX to recirculate and keep the Mash at a constant temperature. A RIMS uses a tube with an electric heating element that is controlled with a PID to recirculate the mash and keep the mash at a constant temperature.

https://www.homebrewtalk.com/f51/rims-dummies-114997/

Click to expand...

I'm not sure that this is correct. All the RIMS that I've seen have had the wort in direct contact with the element.

What he's talking about is a HERMS like everyone else's, except that the coil is in a small water-filled cooler with a heating element, rather than the HLT.

lustreking said:

My HEX is a 1500 watt element in a 2 gallon cooler. It works fine for me.

Click to expand...

Have mine set up the same way. I like the flexibility to have the HEX at one temperature and being able to have my HLT heating water at a different temp. Also, IMO, makes step mashing easier because their is much less liquid to heat up and allows a faster increase.

Found a link that describes what i was talking about earlier, here. I like the idea that its completely separate, and fairly compact. If I was building a HERMS, this is the way I would probably go.

ok I like the idea of being able to change temps a bit faster. However now I'm confused as to how it would be plumbed into the system. Would I then need two pumps? I would be recirculating the wort with one pump and the hot water through the HEX then back into the HLT?

if you're referring to the link in my last post, no only one pump. the heating element is inside that large piece of copper pipe, along with the hex coil and water. Theres no need to move any heating water, but some people might suggest a small stirrer to agitate the hot water (though I don't think it would be absolutely necessary). The hot water sits in the pipe section , you pump your worth through the coil inside it. no different in concept from the HLT HERMS, but smaller, electric, and can swing temps more quickly with a proper sized element.

Ok, so essentially I would need two heating elements. One for the HEX and one for the HLT? Or am I being dumb here?

CoalCracker said:

Ok, so essentially I would need two heating elements. One for the HEX and one for the HLT? Or am I being dumb here?

Click to expand...

Yes, that is correct and also you would need 2 controllers if you want to run them at the same time. One controller for the HLT and one for the HEX

Meh.. I think i'll KISS. I don't really plan on doing step mashes YET, so for the time being maybe I'll just go with the traditional HEX in the HLT.

I dropped the idea of using a dedicated HEX simply because of cost (another element, another locknut, another PID, another vessel, another SSR, another outlet/plug/cable, etc, etc).

That stuff adds up REALLY fast.

Yea this project is adding up REALLY fast and don't care to have any more expenses than I need. Thanks for all of the responses!

for full disclosure, I ended up putting an electric element ONLY in my BK. I use that as the HEX during the mash and have another insulated vessel that I pump the hot water into for temporary holding while then take my 1st mash runnings to the BK.

CoalCracker said:

Ok, so essentially I would need two heating elements. One for the HEX and one for the HLT? Or am I being dumb here?

Click to expand...

If you HEX isn't in the HLT, it's not vital to have precision control over the temp of the HLT, though it does take a little bit of paying attention. Just turn off the element when it gets to the right temperature.

We use a Chin Chiller as a Hex. We run HLT water as the heat source. We have ordered another HLT with a built in HERMS from Stout. We will have knowledge of both. We have thought of using a RIMS type tube to control the temperature of the HLT for the HERMS with a PID once we are at temperature.