Author Topic: Thermometer probe length  (Read 946 times)

Offline ANDREW.GROGAN1

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Thermometer probe length
« on: August 12, 2015, 05:29:17 PM »
I just switched to all grain and had a question.  I am using a 10 gallon igloo cooler setup and I'm ready to invest in a decent thermometer.  I like the thermapen because of its compact size.  The question I have is...How much difference is there between the temperature at the top of the grain bed to the bottom?  I feel like I would need a probe longer then the 4.5" one that the termapen has?  Wouldn't I want to take a reading in the middle of the grain bed?  In a larger batch that would be further down then 4.5"

Offline Stevie

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Thermometer probe length
« Reply #1 on: August 12, 2015, 05:32:58 PM »
I only measure the mash temp at the beginning of the mash after stirring in my grains. At that point, the temp should be fairly uniform.

I use the cheaper $20 thermometer from thermoworks. Honestly one of my favorite pieces of kit under $100.

Offline HoosierBrew

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Re: Thermometer probe length
« Reply #2 on: August 12, 2015, 05:42:40 PM »
I only measure the mash temp at the beginning of the mash after stirring in my grains. At that point, the temp should be fairly uniform.

I use the cheaper $20 thermometer from thermoworks. Honestly one of my favorite pieces of kit under $100.

+1.  OP, I use the same thermometer. It's made by the same company as the Thermopen, has very nearly the same accuracy, for a fraction of the price. It's an absolute steal  :  http://www.amazon.com/RT600C-Super-fast-Water-resistant-Digital-Thermometer/dp/B002GE2XF8
Jon H.

Offline ANDREW.GROGAN1

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Re: Thermometer probe length
« Reply #3 on: August 12, 2015, 05:45:28 PM »
I guess I was just thinking for monitoring temperatures for longer mashes or managing step mashes.  I think what you guys are suggesting would be good for about 90% of what I need it for. 

Offline HoosierBrew

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Re: Thermometer probe length
« Reply #4 on: August 12, 2015, 05:58:28 PM »
I guess I was just thinking for monitoring temperatures for longer mashes or managing step mashes.  I think what you guys are suggesting would be good for about 90% of what I need it for. 

FWIW in a cooler, if you stir thoroughly to reach an even temp and then close the lid and keep it closed, you won't lose over a degree or two during your mash time. No need to monitor temps after closing, assuming you use a cooler. YMMV.

EDIT - This also assumes a single infusion mash.
« Last Edit: August 12, 2015, 06:00:21 PM by HoosierBrew »
Jon H.

Offline johnnyb

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Re: Thermometer probe length
« Reply #5 on: August 16, 2015, 03:01:34 AM »
Since I didn't get one of the super insulated coolers, I toss an old sleeping bag over it once I draw the pH sample @ 5 minutes.

coastsidemike

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Re: Thermometer probe length
« Reply #6 on: August 16, 2015, 03:14:46 PM »
Since I didn't get one of the super insulated coolers, I toss an old sleeping bag over it once I draw the pH sample @ 5 minutes.

What I do is place weights on the top, such that the lid is clamped down tightly.  It seem to have an effect in helping keep heat in.  For an hour long mash the temp stays even.  It also helps to warm the whole thing up by letting it sit for a bit with with the hot water as a precursor to mashing in.

Offline erockrph

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Re: Thermometer probe length
« Reply #7 on: August 16, 2015, 05:22:33 PM »
It also helps to warm the whole thing up by letting it sit for a bit with with the hot water as a precursor to mashing in.
I'd rather just adjust my strike temp to account for the extra few degrees needed to heat up a room temp mash tun. One less step to forget when I'm still half asleep and trying to mash-in.
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Offline 69franx

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Re: Thermometer probe length
« Reply #8 on: August 16, 2015, 06:27:32 PM »
It also helps to warm the whole thing up by letting it sit for a bit with with the hot water as a precursor to mashing in.
I'd rather just adjust my strike temp to account for the extra few degrees needed to heat up a room temp mash tun. One less step to forget when I'm still half asleep and trying to mash-in.
My thoughts as well. Every time I have tried to preheat my tun, I have missed my mash temp. When I just tell beersmith that my tun and grain are at 72 or wherever, it calculates a strike temp that gets me where I want to be very reliably
Frank L.
Fermenting:
Conditioning:
In keg:
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In the works: Hopefully brewing 10 gallons of Pilsner tomorrow for a family reunion in July, then back to IPA and  a barleywine to age

coastsidemike

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Re: Thermometer probe length
« Reply #9 on: August 16, 2015, 07:06:49 PM »
It also helps to warm the whole thing up by letting it sit for a bit with with the hot water as a precursor to mashing in.
I'd rather just adjust my strike temp to account for the extra few degrees needed to heat up a room temp mash tun. One less step to forget when I'm still half asleep and trying to mash-in.
My thoughts as well. Every time I have tried to preheat my tun, I have missed my mash temp. When I just tell beersmith that my tun and grain are at 72 or wherever, it calculates a strike temp that gets me where I want to be very reliably

I would do the guessing on the calculations if I could get it to work for me, but my variables include outdoor temperature and it didn't work well.  I don't care how long the overall setup, and so I do a dry run to set up dead space, drink coffee, checking fittings, more coffee, then mill and mash in.  The mash water is warming up as the tun sits.

For fun: today is a 6.5 gallon porter, 5.3% ABV.  I'm splitting the fermentation with different yeasts (005, 023), one will be chocolate raspberry and the other maybe left alone.  Have to bottle, and so wanting smaller volume of each style.
« Last Edit: August 16, 2015, 09:08:06 PM by surfin_mikeg »

S. cerevisiae

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Re: Thermometer probe length
« Reply #10 on: August 17, 2015, 01:25:58 AM »
I own a Thermapen that I purchased during one of their infamous "open box" sales (the Thermapen that I received did not appear to be an open box item), but just about any accurate thermometer will work for measuring rest temperature.  Your mash bed should not be stratified temperature-wise after you finishing mashing in.  It may become so during the rest, but not immediately after mashing in.

If you really want a Thermapen, you should try to make due with what you have until ThermoWorks runs an open box sale.  I paid $70.00 for my Thermapen, which is still ridiculously expensive for a cooking thermometer.