missing strike water temp every time by 5 degrees.

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miatawnt2b

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I have been using Beersmith to calculate my strike water temps and I am missing it every time by about 5*F. I have been heating my strike water to about 10-15* over temp and adding it to my cooler MLT. I then wait usually about 10-15min for the water to preheat the tun and come down to strike temp before adding the grain. I also enter the actual grain temp into beersmith which usually bumps up the strike temp a few points. Anyhow, even after using this method, after my grain is added, my mash temps are always 5* low.

I am trying to figure out why, and I am wondering if my grain specific heat param got messed up in beersmith somehow. Think someone could check their grain specific heat calculation and let me know? Mine is set to 0.380Cal/gram-C and Volume for 1kg of grain 0.652liters/kg.

Any other thoughts? I have been brewing in my garage which is about 60*F when I am adding grain, and it may take 3-5 min to add it all. I am also wondering if it's dropping that much because the lid is off for that time.

-J
 
I just go about 12 to 13 degrees above my mash temp, wait until it is at 10 degrees above my temp an then add the grains. If I want 154, than I add the water at 167 to 168 wait until it settles to 165 ish and then add my grain..This has worked out great..I also add 175 degree water and let that prewarm my cooler. I used to just go with 165 and grain at same time and found that I would run low around 151..Hope this helps..I do not use beer smith but think if u base something simple as this u should have success. This works great for anything in a normal grain bill.. If u have 15 pounds or plus than this should be taken in to account.

Jay
 
I have always let beersmith tell me my strike water temps and I have always hit the target mash temp quite well. I'm sure you already considered this, but are you sure you're stirring your mash thoroughly and not getting hot/cold spots? Have you tried moving the thermometer around, side to side and surface to bottom, to see if there's a temperature variation?

FYI, the specific heat values are the same in my copy of BS.
 
How is this a problem? Raise your strike temp by 5° above what BeerSmith tells you and call it good. I know that I have to heat my strike water 2° hotter than BeerSmith calls for to hit my mash target, so I do, and I'm balls-on almost every time.

As long as it's consistent, there's no problem at all. The software's never going to give a perfect, exact answer since there are so many variables among different setups/processes.
 
If I read your post right, it seems that you are heating your strike water to what beersmith tells you, then preheating your cooler with it.

If you want to preheat your cooler, You have to preheat it BEFORE adding your strike water. Otherwise your strike water will be colder after pre-heating the cooler.

So either raise your strike water by 5-7 degrees and continue what you are doing, or preheat the cooler with seperate water, THEN add the strike water.

EDIT: I reread your post and i think you are already heating the water ABOVE the strike temp...so either go higher or preheat with hotter water and wait a bit longer...I dunno.
 
I suspect the problem is the grain temperature. The calculator is probably using 70F (AKA room temperature). I always bring my grain into the house a day before brewing, since I store it in a freezer and that really messes up the calculations.
 
miatawnt2b said:
I then wait usually about 10-15min for the water to preheat the tun and come down to strike temp before adding the grain.

I think this is the problem, if you are wating for the water to cool to strike temp and then adding the grains.
 
david_42 said:
I suspect the problem is the grain temperature. The calculator is probably using 70F (AKA room temperature). I always bring my grain into the house a day before brewing, since I store it in a freezer and that really messes up the calculations.

Doubt it. I take the temp of the grain and edit that param in Beersmith also. That usually increases my strike temp about 2 degrees.

Thanks for your help so far everyone. I guess it could be I am not stirring the mash enough... I try to add my grain about 1-2 lb at a time and stir it in. After everything is added, I'll give it a few back and fourths with the paddle and close the lid. Sound like enough?
-J
 
GaryA said:
I think this is the problem, if you are wating for the water to cool to strike temp and then adding the grains.

How is this the problem... maybe I am being unclear.

Say Beersmith calculates my strike to be 172*. I will heat my strike water to 185* and add it to the tun. I then wait for the water to get to 172. This usually takes 10-15 min, and by that time the tun is heated and my strike water is dead on. Make sense?

-J
 
Sorry I was miss reading, thinking you were heating to strike temp adding it to the cooler, and then adding grains.
 
It seems like you've elimnated most of the variables. Are you sure you're measuring the volume of strike water accurately? If you were consistenly short there, you would actually be delivering less heat to the mashtun, and this would make you undershoot. It's not just temperature that's important, but thermal mass.

And when you say you wait for the temp to drop to strike temp, are you sure that's where it stabilizes? Maybe it's still creeping down, continuing to heat the cooler as well as the grain. Try adding your usual amount of hot mashwater (but no grain) to your tun, then close it up and walk away for an hour or more. That should give you an idea about how much heat your tun actually will absorb.

All of this is why I mash in a converted keg - the tun is by definition preheated since I heat it directly.
 
I am pretty confident that I am calculating my water correctly since I pre-measure my mash and sparge water in advance and always hit my boil volume. Your point of the possibility of the tun not being stable yet is a good thought. I just assumed that 15 or so degrees would be enough... maybe not.
-J
 
That's exactly how I've done it since using a cooler MLT. I go in hot, like 180. It takes about 5 minutes (lid closed) for the cooler to absorb about 12F. Now I'm down near 169F which is where BTP usually tells me to strike with. If I actually went through the MLT heat calibration procedure, it should actully be able to tell me the exact temp to strike with (including the initial heat loss) but you'd have to have a stable ambient temp and initial MLT temp for it to work. I'd rather just keep going in hot and waiting for it to stablize. If it's low, I'll add a touch of boiling water. If it's high, I'll stir with the lid open.
 
miatawnt2b said:
How is this the problem... maybe I am being unclear.

Say Beersmith calculates my strike to be 172*. I will heat my strike water to 185* and add it to the tun. I then wait for the water to get to 172. This usually takes 10-15 min, and by that time the tun is heated and my strike water is dead on. Make sense?

-J

I thought you weren't suppose to add the grain to the water. I read you should always add the water to the grain.
 
miatawnt2b said:
How is this the problem... maybe I am being unclear.

Say Beersmith calculates my strike to be 172*. I will heat my strike water to 185* and add it to the tun. I then wait for the water to get to 172. This usually takes 10-15 min, and by that time the tun is heated and my strike water is dead on. Make sense?

-J

That may be the problem right there....

Lets just say that the MLT and water temps have not ballenced out and is still dropping (ie. the tun is not heated all the way yet) and then you add the grain droppin the water temp more and over the time it takes you to get all the grain in and mixed up the MLT is still pulling heat from the water..

I add 5 gallons of water to my MLT at 180* and I leave it in there until my strike water is up to temp (15 minutes or so) this puts my MLT at about 100* give or take depending on what it started at). Then I drain, add the strike water then grains and mix. and I hit my temps right on the last 4 or 5 brews doing it this way.
 
Bobby_M said:
I've always felt that preheating then dumping the water was a waste of water and energy.

It's so minute a "waste", though - no more a waste than when my wife makes a cup of tea and then forgets about it and ends up dumping it. It's easy for me to preheat, though, since I mash in the kitchen; I put the kettle on and bring it to a boil (or close), then add maybe a pint of water to the cooler and slosh it around. It'd be more a PITA if I was heating that water on the propane burner.
 
FSR said he puts 5 GALLONS @ 180 in there to preheat. That's like 25k BTU hours of waste. The point I'm making is that you're already looking to put hot water in there for strike, why not heat that water 10 degrees hotter and let it cool. That's a lot more efficient than heating twice the amount of water.

I know everyone is going to do what works for them, but I've had no problems preheating with my strike water.
 
It's also a waste of time. Heat water just to preheat....then heat more water? Screw that.

I use the heat 10-15 degrees above strike temp, put in cooler, let cooler preheat, mix grains in when strike temp arrives. Works good for me.
 
Shouldn't the hot water heat the tun pretty much instantaneously? The whole point of the equipment adjustment option in BeerSmith is so you don't have to preheat the mash tun at all, you just add the water to the tun and grains and the temp ends up around the right temp you need.

I use BeerSmith. It usually gives me values in the upper 160s to lower 170s in order to hit the lower to mid 150's for the mash. This is with the equipment adjustment on and without preheating the mash tun.

I'll usually let the temp go a few degrees above what BeerSmith recommends for wiggle room. That way if the mash temp is off, it will be too high rather than low and I can easily add some cool water to correct the temp.

Looks like the easiest solution here is simply raise your water temp 5 degrees more. Or maybe your thermometer is off.

-Jon
 
Bobby_M said:
FSR said he puts 5 GALLONS @ 180 in there to preheat. That's like 25k BTU hours of waste. The point I'm making is that you're already looking to put hot water in there for strike, why not heat that water 10 degrees hotter and let it cool. That's a lot more efficient than heating twice the amount of water.

I know everyone is going to do what works for them, but I've had no problems preheating with my strike water.

I'm also heating a 20 gallon cooler.
 
iamjonsharp said:
Shouldn't the hot water heat the tun pretty much instantaneously? The whole point of the equipment adjustment option in BeerSmith is so you don't have to preheat the mash tun at all, you just add the water to the tun and grains and the temp ends up around the right temp you need.

I use BeerSmith. It usually gives me values in the upper 160s to lower 170s in order to hit the lower to mid 150's for the mash. This is with the equipment adjustment on and without preheating the mash tun.

I'll usually let the temp go a few degrees above what BeerSmith recommends for wiggle room. That way if the mash temp is off, it will be too high rather than low and I can easily add some cool water to correct the temp.

Looks like the easiest solution here is simply raise your water temp 5 degrees more. Or maybe your thermometer is off.

-Jon

BTP allows for this too but as I mentioned, it's highly dependent on the prior temp of the cooler. If you have it sitting in your 40F garage over night, it's going to require a lot more initial heat than if it was at room temp. That's what people in seasonal areas have to deal with. I know that if I put 170F water in my cooler, it will drop to about 160 in 5 minutes. Once the grain goes in, I'll be way down in the 140's. I need an equilized temp of about 169 for most grain bills to settle at 153F.
 
BREW N QUE said:
I also drain the water I use to preheat, but I drain it into my HLT and use it fr my sparge water.

This is what I do..

I fill 5 gallons (yes Bobby 5 whole gallons:D ) in my HLT from my hot water line so it goes in at around 120*. I heat it to 180 and transfer it to the MLT and close the lid.
Then as that's sitting I add my strike water to my HLT and fire it up. When it hits the temp I need (170-175* most of the time) I drain the MLT to my boil kettle.
Then I transfer the strike water to the MLT and add grain. Mix it up until I hit the temp and I can't find any more hot/cold spots. Close it up and set the timer.

Then I fire up the kettle and bring that water I use to preheat to a boil for 10-15 minutes.
While that's boiling I add in my mashout water to the HLT and fire that up.

I then drain the boiling water in the kettle thru my CFC to clean it and sanitize it.

And I think you know the rest.

So yes I use a little more LP but really not that much. I have two burners and two LP tanks and I get 4 to 5 (10 gallon) brews out of the tanks.
 
Bobby_M said:
BTP allows for this too but as I mentioned, it's highly dependent on the prior temp of the cooler. If you have it sitting in your 40F garage over night, it's going to require a lot more initial heat than if it was at room temp. That's what people in seasonal areas have to deal with. I know that if I put 170F water in my cooler, it will drop to about 160 in 5 minutes. Once the grain goes in, I'll be way down in the 140's. I need an equilized temp of about 169 for most grain bills to settle at 153F.

Sounds like BeerSmith's calcs aren't too good on getting the right temps in this case then. Looks like for a cooler, the specific heat value may need to be increased (BeerSmith assumes 0.3 for plastic). That or the mash tun weight needs to be factored in better.
 
iamjonsharp said:
Sounds like BeerSmith's calcs aren't too good on getting the right temps in this case then. Looks like for a cooler, the specific heat value may need to be increased (BeerSmith assumes 0.3 for plastic). That or the mash tun weight needs to be factored in better.

Yes you have to play around with that.
If you are talking about a plastic bucket then it would not take much to heat it being that it's less then .125" thick but my cooler wall is almost 1.5" thick so it takes a lot to warm that up.

I "think" I have mine set to the 0.3 for plastic but I have the weight set to like 40#s to get it right.

So you add the grain to the water as well? Interesting.
Yes, I have done it the other way but I found I lost more heat when adding the water. Because I was mixing while the HLT was draining.
Now I can run the hose into the MLT close the lid down on it so it's not so open and drain. Once all the water is in there I dump in half the grain and mix then add the rest and mix.
 
Is Beersmith compensating for Thermal Loss of Mash Tun?

Because if you're heating your mash water above strike temp and adding it all in, letting it sit until strike temp, then adding grain, your thermal loss should be zero.

I would think that would make your mash temps higher though as Beersmith would ask for higher temps to compensate for loss... hmmmm...

Maybe your thermometer isn't calibrated for mash temps? A Thermometer can be calibrated for boiling and freezing but still be off elsewhere.
 
SPLASTiK said:
Is Beersmith compensating for Thermal Loss of Mash Tun?

Because if you're heating your mash water above strike temp and adding it all in, letting it sit until strike temp, then adding grain, your thermal loss should be zero.

I would think that would make your mash temps higher though as Beersmith would ask for higher temps to compensate for loss... hmmmm...

Maybe your thermometer isn't calibrated for mash temps? A Thermometer can be calibrated for boiling and freezing but still be off elsewhere.
In Beersmith you tell it what the temp of the MLT is, you also tell it what it's made of and how much it weighs so that it can figure out how much temp the MLT will pull from the water.
 
SPLASTiK said:
Is Beersmith compensating for Thermal Loss of Mash Tun?

Because if you're heating your mash water above strike temp and adding it all in, letting it sit until strike temp, then adding grain, your thermal loss should be zero.

I would think that would make your mash temps higher though as Beersmith would ask for higher temps to compensate for loss... hmmmm...

Maybe your thermometer isn't calibrated for mash temps? A Thermometer can be calibrated for boiling and freezing but still be off elsewhere.

I do not use the option in Beersmith to calculate for the temp of the equipment. The thermometer I have been using is a small Taylor analog dial... not exactly a piece of junk, and it is indeed calibrated and reads perfectly at both 32 and 212. I would assume that it would also be accurate throughout that range, but who knows.

-J
 
Try ignoring beersmith.

Just investigate these questions:
How much heat your mash tun will sap from the strike water.
How much heat the grain will sap from the water before hitting the target.
How much water you use.
How hot that water is.

Always use the SAME amount of water per pound of grain. Only change the temperature.
 
I have failed to find this mentioned in the previous posts so I'll throw it in there for good measure even though I do not use Beersmith and speak ignorantly.

Beersmith may give you a field in which you can enter the temperature of the MLT but does it give you a field in which you can enter the dimensions, type and thermal efficiency? Does it take into account your altitude above sea level? It seems to make sense to me that a plastic bucket, stainless steel keg, aluminum pot, round 5 gallon cooler and square 10 gallon cooler would all require different amounts of energy to preheat and would all lose heat at differing rates at different altitudes so why would a one value fits all field be considered suitable for highly accurate strike temperature calculations?

Remember, brewing software is just a tool and is only as reliable as the information you give it and the information that it accepts. I think we all can get hung up on what should ideally happen according to our calculations and according to what happens when other people brew with their own systems. I myself never take software calcs as gospel but instead I have chosen to evaluate my brew system through experience. Keep a log, as it seems you may have, an adjust accordingly.
 
Bobby_M said:
FSR said he puts 5 GALLONS @ 180 in there to preheat. That's like 25k BTU hours of waste. The point I'm making is that you're already looking to put hot water in there for strike, why not heat that water 10 degrees hotter and let it cool. That's a lot more efficient than heating twice the amount of water.

I know everyone is going to do what works for them, but I've had no problems preheating with my strike water.

+1 for Bobby........

I put water in the mash tun over the strike water temp and let it equalize and when it is at the stable strike temp I add the grains. Mix and wait 15 minutes and stir and take the temp and it should be spot on (mash temp).
 
WBC said:
+1 for Bobby........

I put water in the mash tun over the strike water temp and let it equalize and when it is at the stable strike temp I add the grains. Mix and wait 15 minutes and stir and take the temp and it should be spot on (mash temp).


+2, I did the same thing on Saturday and it worked well. No reason to waste that water/gas when you don't have to...
 
Bobby_M said:
I know everyone is going to do what works for them, but I've had no problems preheating with my strike water.

Likewise. ProMash will take into account the heat capacity and temp of your mash tun and give you an adjusted strike water temp (ie how hot does the water need to be to preheat the tun and get the mash to the target temp).

Takes a little trial and error to dial in the heat capacity, but after that it works like a charm.
 
FSR402 said:
I add 5 gallons of water to my MLT at 180* and I leave it in there until my strike water is up to temp (15 minutes or so) this puts my MLT at about 100* give or take depending on what it started at). Then I drain, add the strike water then grains and mix. and I hit my temps right on the last 4 or 5 brews doing it this way.

I do the exact same thing, and I'm dead on every time.
 
saul said:
Try ignoring beersmith.

Ignore Beersmith, not Brewsmith. :D

I use promash to calculate my mash temps, but I also fudge the numbers all over the place. I estimate my grain temp at least 5 degrees below ambient temp, I preheat my mash tun with seperate water and then pour it out before adding strike water that is about 2 degrees over, and I usually add about one half to a whole quart of water extra. Seems to come out just right.
 
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