Author Topic: Kettle thermometer placement  (Read 5802 times)

Offline euge

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Kettle thermometer placement
« on: July 13, 2011, 06:46:28 PM »
I just got 2 Blichmann BrewMometers and want to place one in my 80qt. Any ideas on placement? I'm only utilizing half the capacity of this kettle. I'm not totally adverse to using both thermometers.
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Offline denny

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Re: Kettle thermometer placement
« Reply #1 on: July 13, 2011, 07:00:57 PM »
What is it that you want the thermometer to tell you?  That could help determine the placement.
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Offline richardt

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Re: Kettle thermometer placement
« Reply #2 on: July 13, 2011, 07:27:45 PM »
Euge,
I put one of those Blichman Brewmometers in on my 20 gal (80 qt) SS kettle a month or two ago.
The instructions said to put it 6 inches above the bottom of the kettle so that it would:
1.) sample the middle of the wort volume (better temp readings)
2.) be far enough away from the bottom of the kettle (and the burner) to prevent damage to the thermometer housing (which must remain dry and below 140 F).  As a guide, you need to be able to hold your hand at that 6" level for at least two seconds when the kettle is on the burner (burners are on) and not feel the need to yank it away.

Exceptions are permitted so long as you have a heat shield made (not included) that protects the housing of the thermometer from the heat of the burner.  I chose not to do that.  I put it in at 6 inches from the bottom directly over my spigot (no problem operating the spigot).  The thermometer is only useful when I have a full pot of strike water or wort (10 gallon batch). 

This creates a problem when I only want to heat 8 gallons of strike water (not the full 17 gallons).  The water level (for 8 gallons) barely reaches the probe.  I boil the remaining 8 or 9 gallons when I am 40 minutes into the mash so it is ready for mashout and sparging.  (same problem with temp readings as the water level is just at the level of the probe).  Similar problem occurs when I collect the first runnings and want to start heating the wort while collecting the second runnings into another pot (a 5.5 gallon SS kettle).

I would recommend mounting the thermometer at 4 inches (just high enough so that the circumference of the dial doesn't interfere with the spigot) or slightly off center and use a heat shield (aluminum foil?).  I can't imagine how low you'd need to put it (probably 2 inches up from the bottom) if you were only doing 5 gallon batches in a 20 gallon pot.  You'd definitely need a sturdy heatshield if you did that.

Offline euge

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Re: Kettle thermometer placement
« Reply #3 on: July 14, 2011, 12:14:19 AM »
Ahhh. Thanks.

I want it to tell me the general temp of the water or wortfor both heating and cooling. Don't plan to mash with it for the time being.

The six inches seems about right. My spigot is three inches above the bottom and three over that would work. So I was thinking of installing the second one higher up for when I do bigger batches.

I've started recirculating with the pump when heating and cooling and am tired of scalding myself when reaching in to take a temp reading.
The first principle is that you must not fool yourself, and you are the easiest person to fool. -Richard P. Feynman

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Offline narcout

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Re: Kettle thermometer placement
« Reply #4 on: July 14, 2011, 01:45:10 AM »
I've got a brewmometer installed 6 inches up (the hole is six inches up anyway) from the bottom of a 10 gallon megapot.  I've found that even with a heat shield I can't keep the case from getting over the max temperature (I believe it is due to the amount of heat coming through the wall of the kettle).  The result is that the brewmometer gets a bit cloudy by the end of boil, but it always seem to go back to normal after a few days (I've had it about 6 or 8 months, and it's still functioning perfectly).
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Offline richardt

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Re: Kettle thermometer placement
« Reply #5 on: July 14, 2011, 02:35:30 AM »
The instructions that come with the Brewmometer also say to keep water off the thermometer housing when using and cleaning the BK.  By your description of the glass getting a little cloudy during use it sounds like there's moisture trapped inside there somehow.  If it didn't get wet from your use, then are you storing it someplace humid or damp (e.g., your garage) that's not air conditioned?

If there's ever an upgrade to the Blichmann Brewmometer, I'd seriously recommend waterproof housing and better heat shielding be included in the design.

Offline narcout

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Re: Kettle thermometer placement
« Reply #6 on: July 14, 2011, 09:11:00 PM »
By your description of the glass getting a little cloudy during use it sounds like there's moisture trapped inside there somehow.

I think in the manual it says that if the brewmometer gets too hot the water tight gaskets will deform a bit and allow moisture into the unit.  I've tried a variety of heat shields without success.  However, the unit always dries out after a few days and still functions perfectly.  For a $30 piece of equipment, I'm not too worried about it.
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Offline euge

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Re: Kettle thermometer placement
« Reply #7 on: July 15, 2011, 06:30:54 PM »
Drilled out 1/2" hole(s) with a step-bit. One 6" up and the other 5" up from the bottom. If needed I can move the brewmometer up for the larger batches, but 5" up is just about ideal for those 7 gallon batches.

Used it for the first time last night. Excellent performance from the thermometer and I knocked out an AG batch on the stove in 5 hours flat chilled to 64F.

No problems with moisture or overheating. Thanks for the responses Guys.



The first principle is that you must not fool yourself, and you are the easiest person to fool. -Richard P. Feynman

Laws are spider-webs, which catch the little flies, but cannot hold the big ones. -Anacharsis