Pre-heating the mash tun?

[Newton]

So I've done 3 batches of all grain and I've been "pre-heating" the mash tun (36 quart Coleman Extreme) with a couple of quarts of boiling water for about 5 minutes. I then add my grain and water (about the 168-170 range), stir, and take a temperature reading. My temps have all come out high like at 160 and I need to add more (cold) water to bring my mash temps down to 152. Its worked out all three times but I end up with a small batch sparge and an efficiency of like 65%. Should I not pre heat my mash tun? Any suggestions?

Ben

 

[Frodo]

I've only done a couple of AG batches - the first time I tried pre heating the tun, adding the grain then the water, but I came out really low on the mash temp. The second time I put the water in first, got it to stabilize at what the strike temp was supposed to be then added the grain. Hit the temp dead on. The second method is what I'm doing from now on.

 

[mojotele]

Well, first, don't put boiling water in your plastic cooler. It can deform and even crack the liner.

The method that works best for me is similar to what Frodo mentioned:

1. Heat up your strike water to maybe 180*F.
2. Dump it all in your cooler.
3. Let it sit for as long as it takes to get to your strike temperature.
4. Add grain.

That should get you really close to your target mash temperature, and you need to heat up less water.

 

[RedGlass]

So I've done 3 batches of all grain and I've been "pre-heating" the mash tun (36 quart Coleman Extreme) with a couple of quarts of boiling water for about 5 minutes. I then add my grain and water (about the 168-170 range), stir, and take a temperature reading. My temps have all come out high like at 160 and I need to add more (cold) water to bring my mash temps down to 152. Its worked out all three times but I end up with a small batch sparge and an efficiency of like 65%. Should I not pre heat my mash tun? Any suggestions?

Ben

How are you calculating your strike temp? For example, if you're using software and calibrated your MLT's heat loss without pre-heating, then choosing to pre-heat will leave you with higher temps...

 

[phidelt844]

Personally, I preheat 3g to 160 degrees and leave it in there until I've got my strike water heated, which I get to ~175 degrees. When I add my grains, I drop right down to 152-155 range. Since every set up is different, however, you're going to have to find what temps work on your system. You can preheat or you can not preheat, but you are going to have to adjust your strike water temps to match which method you choose to use.

 

[Newton]

So John Palmer says to add water to grains and not the other way around. Is this outdated info?

 

[mojotele]

So John Palmer says to add water to grains and not the other way around. Is this outdated info?

Yeah, that's been brought up before. The consensus is that there's really no difference or not enough difference to be noticeable. I've made several batches now adding grain to water, and they've all turned out great.

 

[jewillia]

I'm going to have to try adding grain to water next time I mash. I had been using John Palmer's advice of adding water to grain also, but I never hit my temp off the bat. I wondered what the harm would be in adding grain to water. If it's really nothing, then I'd rather do it that way, since you can wait to add the grain until your water temp has stabilized.

Does the room temperature grain bring the water temperature down much? I'm assuming it depends on the size of your grain bill.

 

[mjap52]

Sorry to res this thread from the dead, but I've got a 70 quart cooler and like to do the occasional 5 gallon batch in it. I've been thinking of boiling 1.5 gallons of water and adding it to the tun the night before brew day to preheat it so it's one less thing to forget in the AM. Any thoughts on this?

 

[billl]

Most of the plastics in coolers are only heat rated to 180 or so. As noted above, adding boiling water to them is generally a bad idea.

I'd recommend just measuring the water out the night before and putting it in a pot on the stove.

 

[mjap52]

Most of the plastics in coolers are only heat rated to 180 or so. As noted above, adding boiling water to them is generally a bad idea.

I'd recommend just measuring the water out the night before and putting it in a pot on the stove.

I did not know that! Thanks for the heads up!

 

[jestmaty]

When I'm a bit high on the mash temp, I just go to the fridge, get a big cup o' ice from the ice maker then dump, stir, take temp reading. Not too much ice or you'll be at the other end.. too low!

Yesterday's brew called for 4.5 gallons of strike water and I dumped maybe 1 1/2 cups of ice in my 158-159* mash to get it down to 152*

As always, remember, ymmv. Use less ice than you think you need and add small bits and stir in COMPLETELY after each ice dump

 

[Kingfish]

When I'm a bit high on the mash temp, I just go to the fridge, get a big cup o' ice from the ice maker then dump, stir, take temp reading. Not too much ice or you'll be at the other end.. too low!

Yesterday's brew called for 4.5 gallons of strike water and I dumped maybe 1 1/2 cups of ice in my 158-159* mash to get it down to 152*

As always, remember, ymmv. Use less ice than you think you need and add small bits and stir in COMPLETELY after each ice dump

I had to do this with my last brew. Thought I would preheat the tun but forgot to take that into account with the strike water temp.

 

[Revvy]

I use hot tap water. Just a couple gallons. It's especially good idea for outdoor brewing in the winter.

 

[wherestheyeast]

Most of the plastics in coolers are only heat rated to 180 or so.

Can you provide a reference for this? I've been searching for specifics from the cooler manufacturers and haven't had any luck.

Thanks

 

[VonAle]

I added 185 degree water to my 40 qrt igloo and the now side walls are bubbled and deformed.

I won't do that again.

 

[CKing]

I use hot tap water. Just a couple gallons. It's especially good idea for outdoor brewing in the winter.

I started out filling my mash tun with hot tap water which helped.
Then I decided to adjust my settings in Beersmith using 60 degrees for my equipment and grain temperature which are stored and used in my basement.
This adjustment has proven more effective for me.

 

[Frodo]

I added 185 degree water to my 40 qrt igloo and the now side walls are bubbled and deformed.

I won't do that again.

Mine did that too, but just the first time. It seems like it's done all the popping/creaking/deforming it's going to do in it's lifetime.

 

[kh54s10]

I have my equipment outdoors now. During the summer I just use a bit of heated water, maybe 110-120. During the winter I was using 170 + and a larger amount of water.