HERMS -Temperature

[PommyIan]

Hello all.
I've pondered this for a while but just can't decide. When recirculating the mash with a herms where should the mash temp for control be measured?
1. At the mash tun exit?
Seems logical but the water entering the mash tun will be higher, hence mashing some grain at a higher temp...
2. At the mash tun entry point.
Again logical but temp will be lost through yhe mash and again some grains will be mashed at a lower temp this time.

Thoughts and experiances welcome......

 

[gusty]

Ive got a bimetal gauge in the mash tun that "monitors" the mash temp, but I have a temp gauge on the outlet of the HERMS coil as well which I use to control the temp, and I only lose about .2-.1 deg through the mash but to answer your question where to control it front?, it should be on the outlet of the coil to prevent over shooting your temps.

 

[Smokomark]

It must always be located were the highest temperature is in the whole system - the outlet of the herms coil.
The rest can lag behind but will eventually catch up.

If you measure in the grain bed there might be 2 or 3 degrees difference between the that and the herms outlet resulting in a much fuller body beer.

 

[Cortez The Killer]

I've got a Kmart kettle with a stainless coil in. I'm measuring on the coil output too which would be the warmest point in the loop.

The mash tun probably lags by about a degree, once everything stabilises, behind the HERMS output.

The the mash temp repeatability offered by a HERMS' is probably it's primary benefit so theoretically any data point along the loop would be usable as you would adjust the temp up or down if you found the resulting beer too sweet or too dry.

Having the probe at the coil output would provide the most meaningful / real time readings for the controller to switch the element on and off.

Cheers

 

[mudd]

I've got a Kmart kettle with a stainless coil in. I'm measuring on the coil output too which would be the warmest point in the loop.

The mash tun probably lags by about a degree, once everything stabilises, behind the HERMS output.

The the mash temp repeatability offered by a HERMS' is probably it's primary benefit so theoretically any data point along the loop would be usable as you would adjust the temp up or down if you found the resulting beer too sweet or too dry.

Having the probe at the coil output would provide the most meaningful / real time readings for the controller to switch the element on and off.

Cheers

hey Cortez, do you have a pic of the kettle. I was thinking of something similar.

 

[S.E]

hey Cortez, do you have a pic of the kettle. I was thinking of something similar.

h34r:

 

[Crusty]

Hello all.
I've pondered this for a while but just can't decide. When recirculating the mash with a herms where should the mash temp for control be measured?
1. At the mash tun exit?
Seems logical but the water entering the mash tun will be higher, hence mashing some grain at a higher temp...
2. At the mash tun entry point.
Again logical but temp will be lost through yhe mash and again some grains will be mashed at a lower temp this time.
Thoughts and experiances welcome......

The temperature difference would also apply to an esky mash tun where you need to add strike water hotter than your desired mash temperature. It will quickly absorb that higher temp then stabilize. The same situation will apply to your Herms but again, rather quickly the mash tun temp will stabilize. You definitely want your temp probe at the hottest point in your loop & that's at the Herms outlet.

 

[MAX POWER]

How do you measure at the outlet? I have a copper coil I plan on using in a 10l crown urn and would like to use quick disconnects throughout.

What do I need to achieve this?

 

[sp0rk]

How do you measure at the outlet? I have a copper coil I plan on using in a 10l crown urn and would like to use quick disconnects throughout.

What do I need to achieve this?

Most people use a Tee fitting, the wort flows straight through and the temp sensor comes in through the side (or the top if you're feeding off on a 90° angle)
Like this (the cable gland on top is where the probe will go in)

 

[MAX POWER]

Cheers. Thanks mate.