Temperature probe position

[Arbe0]

OK, I have my heating elements for my HLT and Brew Pot installed in my electric brew system.
I have seen a few ways to install the Temperature probes. Some are right in the pot others are in a NPT tee fitting inline with the ball valve.
I am looking for what you guys, that have built your systems, have done and what you feel works better.

 

[haydensitmonchai88]

I put mine joined into a stainless steel tee to the ball valve that runs down to the pump. because i have a pump for each kettle i alway recirculate to get a even temp.

I had a keggle set up before with the probe in the thermowell about 6 inchs from the bottom. worked fine to but if your not recirculating just stir the water every now n then

Happy brewing

 

[BeardedBrews]

Most of brewing is cleaning, making the probe easy to remove makes cleaning easier.

I had mine in a tee and it sucked to get it out to clean. Now it's mounted in the kettle wall using a silicone gasket instead of Teflon tape and I'm much happier.

 

[processhead]

I installed the temp sensor for my InkBird controller in a extra corny-keg dip tube I had laying around. Its sealed at each end with silicon RTV and make it convenient to just set it in my keggle based HLT.

When its in use, the actual sensor sits near the bottom of the HLT.

 

[Arbe0]

a little more information: HLT will (not yet) have a herms coil so the hot water will recirculate around the HERMS coil from a tube on top pulled up from the ball valve (with a pump). this should keep the water temperature close to the same top and bottom. The HERMS coil will have the wort in it, recalculating in the HLT water, to keep it or raise the temp of the wort in the mash tun.
The boil pot is …. well.. a boil pot, just need to have a nice rolling boil I it.
The whole system is controlled with a 240V 30 amp control panel with a PID controlling the water temperature in the HLT for the HERMS coil, and one for the boil pot.
My thought about this is the RTD probe (temperature sensor) for the HLT should be in a Tee, inline with the ball valve, so it measured the temperature out of the HLT recirculating to the top of the HLT. And the boil pot it could be in the side of the pot.
Or should I be reading the wort temperature in the mesh tun?

 

[haydensitmonchai88]

Yeah that sounds about right. i have both my probes in tees in hlt and boil kettle because im recirculating off both pumps always so it makes for a nice steady temp. But if your only using one pump just chuck a thermowell in your kettle n call it good.

If you put it in the tee section make sure to get quick disconnect rtd probes so you can take them in and out for cleaning.

Theirs a crap load of ways to do it just need to work out what is best for your system mate

 

[sicktght311]

I have a 3 vessel herms as well.

My thought is you want your probe wherever the wort is moving, and you want it measuring the liquid as its going back into the mash tun so you're constanlty recirculating wort that is at the temperature you want to hold at.

SO, I have analog thermometers in the sides of my HLT and MT to monitor, but the controller reads the temp in a Tee coming out of the Herms coil, and controls the HLT element from there.

My boil kettle's temp probe is right in the side of the pot

 

[Arbe0]

yep... decided on HLT will have probe inline with the ball valve and boil pot in the side of the pot.

 

[BeardedBrews]

My thought is you want your probe wherever the wort is moving, and you want it measuring the liquid as its going back into the mash tun so you're constanlty recirculating wort that is at the temperature you want to hold at.

This is true for herms for sure. The exception would be if you're directly heating the wort like you would in a RIMS, Direct Fire Mash, or BIAB system. In those cases you'd want the wort temp probe to be fairly close to the element so that you don't over heat due to temperature lag from slow recirculation or inadequate mixing.

Edit: I should add that you do still want to measure the temperature at all the other places you described to make sure you're system is working the way you think it is. I'm strictly speaking about how to get the best performance out of the temperature controller. You want the controller to have nice tight control over what it's doing at the element, and then you just stir/mix/recirculate well to get the rest of the system to stay close to that temperature.

 

[Arbe0]

I would think the bottom line for the Herms coil and HLT is to make sure the temperature is what I want into the mash tune after all the Herms and hoses and adjust the PID to reflect that.

 

[daveerickson]

I would think the bottom line for the Herms coil and HLT is to make sure the temperature is what I want into the mash tune after all the Herms and hoses and adjust the PID to reflect that.

Wouldn't the temp on the outlet of the HERMS be the same as in the HLT? It seems to me that with a sufficiently long coil that would be the case. Can someone with this setup weigh in on how it actually works?

 

[kevink]

The probe should go at the mash tun inlet since that is what you want to control the temp of. Putting it anywhere else will be less precise. It doesn't matter what the hlt temp is. The pid will figure out what is needed to make the mash the correct temp.

 

[doug293cz]

The probe should go at the mash tun inlet since that is what you want to control the temp of. Putting it anywhere else will be less precise. It doesn't matter what the hlt temp is. The pid will figure out what is needed to make the mash the correct temp.

The HLT temp doesn't matter until it gets over about 160°. At that point you will start denaturing most of the enzymes in the wort that goes thru the recirculation loop. Remember, enzymes denature even at mash temps, and as the temp increases, the rate of denaturing increases rapidly. There is nothing magic about the 168° mash out temp. It's just that at that temp, essentially all of the alpha amylase will be denatured in about 10 minutes.

Brew on

 

[kevink]

Okay, but that is kind of irrelevant. My point is that the exact temp of the HLT does not matter, so that is not the place to put the temp probe. The PID will make the temp of the wort where you want it if you put the probe at the MT inlet. You will not have more than a few degrees difference between the HLT and the MT inlet unless your HLT is 100 feet away from your MT and you push the wort through uninsulated tubing which of course nobody does.

 

[daveerickson]

It seems some people have different number of temperature probes, which may account for some placement differences. My questions below are coming from the point of a HERMS system, but may be applicable to others. Each question builds upon an assumption that the previous question is true.

1. Is it accurate to think that the temp of wort leaving the HERMS coil is equal to the HTL temp? It seems that after 50' this would be the case, but I haven't tested and would love input from someone with probes mounted this way.

2. Is there temperature stratification in the grain bed? It seems a 4ish degree difference between the outlet of HLT and MTL would more likely be caused by going through the grain bed than while going through a 4' hose into the MLT.

3. Would controlling the amount of stratification, say by adjusting flow rates, be a way to affect conversion characteristics which would impact fermentability? I have no observations on this one, it just seems like it could be yet another variable to play with.

 

[day_trippr]

1 - in my experience with a 50' 1/2" SS hex recirculating between 2 and 3 gpm the wort exit temperature is the hlt bath temperature.
2 - I recirculate at that rate to keep the mash temperature as equalized top to bottom as possible. Slowing the rate does cause greater temperature differential.
3 - see above.

reference: 20 gallon SS kettles for hlt/mlt/bk...

Cheers!

 

[Blazinlow86]

It seems some people have different number of temperature probes, which may account for some placement differences. My questions below are coming from the point of a HERMS system, but may be applicable to others. Each question builds upon an assumption that the previous question is true.

1. Is it accurate to think that the temp of wort leaving the HERMS coil is equal to the HTL temp? It seems that after 50' this would be the case, but I haven't tested and would love input from someone with probes mounted this way.

2. Is there temperature stratification in the grain bed? It seems a 4ish degree difference between the outlet of HLT and MTL would more likely be caused by going through the grain bed than while going through a 4' hose into the MLT.

3. Would controlling the amount of stratification, say by adjusting flow rates, be a way to affect conversion characteristics which would impact fermentability? I have no observations on this one, it just seems like it could be yet another variable to play with.

From what I've read it depends on your configuration but at least in my herms setup the temp coming out of my 50ft stainless coil matches the temp my HLT is set at exactly with zero offset required as well as the mlt output typically matches the mlt input. I actually don't even have a thermometer in my mash tun anymore as it was redundant. I turn the mash liquid over pretty quickly so I don't see any stratification however I mill on the corse side to allow that and avoid channeling. If you prefer to mill tight for better efficiency on a circulating setup you might have issues. I tried both ways and my efficiency didn't change but I did have hearing performance issues with a tight mill setting. Cheers

 

[daveerickson]

Thanks for the feedback and confirming I'm at least on the right train fo thought.