[tonydl77]

Greeting fellow brewers.
I am new to home brewing and have a rookie question. when using a cooler as a mashtun, how do you increase the temperature when the temperature drops? Is it as simple as pouring in some more boiling water or what is the correct way of doing this?

[Stevie]

Welcome

Don't worry about a few degree drop over the course of the mash. If you miss your target and want to adjust, boiling water or ice both work well.

I loose about 1-2° over 60 minutes. Lower when it's hot, higher when it's cold.

[tonydl77]

For some strange reason, I lost almost 7 degrees, so I added about two cups of boiling water midway through the mash but I wasn't sure if that was the right way of doing it. I suppose it might be easier to control if you mash in a kettle on a stove.

[duboman]

7 degrees seems like a lot and it could be stratification of the mash and where you are taking the temp from. Also be sure your thermometer is properly calibrated.

You can always wrap your MT in a blanket during the mash if it really is losing that much heat over 60 minutes. It is also a good idea to pre-heat your mash tun prior to dough in.

[Stevie]

Coolers work great.

How often were you opening the cooler? I measure when I mash in and sometimes at the end to see where it is at. No need to open it more often in my opinion.

Did you pre-heat the cooler or account for the cooler sucking some heat out of the strike water? 7 degrees is about my target above strike, so maybe that is where you lost your heat.

Did you stir really well when mashing in?

[Joe Sr.]

I haven't been pre-heating the mash tun, but I'm overheating my strike water like Steve.

I'm going a fair bit higher than 7 degrees, though.

My recollection is strike at 170 gave me a mash temp of 155, maybe slightly less.

Over a 60 minute mash, I lost maybe 2 degrees.

[Stevie]

To clarify, I go about 7-10° over my strike temp, not mash temp.

[tonydl77]

I pre-heated the mashtun by pouring boiling water in it and letting it sit for a few minutes. I then poured out the water before mashing in. When I mashed in, I stirred until there were no dry or clumpy grain. I closed the mashtun and opened it about once every ten minutes to take a temperature reading. I will most definitely try the blanket idea and also not opening the mashtun as often. @duboman - what do you mean by "thermometer is properly calibrated."?

[Joe Sr.]

To clarify, I go about 7-10° over my strike temp, not mash temp.

Reading comprehension is not my strong suit, apparently.

[HoosierBrew]

Agreed with all the above. I'd add that the way that WILL maximize your temp loss from start to the end of the mash is to open the lid during the mash. Stir thoroughly enough to reach a consistent temp, close the lid and wrap in a blanket or sleeping bag if desired, and just walk away. You'll lose a degree or two over the mash - no need to worry, beer will be fine. Good luck !

[Joe Sr.]

Agreed.  Don't open it so often.

It's like opening your oven, you let the heat out.

[tommymorris]

When I mash, I measure the temp after stirring then close the lid and wait 1 hour. If I measure the mash temp right at the end of the hour without any stirring (immediately after opening lid) I invariably have lost less than a degree (often nothing). As soon as I stir the mash, the temp drops several degrees. Maybe there was stratification and the average temp of the whole mash had dropped over time or maybe the stirring released heat. I don't know.

But, what ever is happening doesn't seem to have any effect on the beer or my efficiency, so, I have never worried about it.

When two people have different experiences, I wonder if their methods are the same. Is one person stirring before taking a post mash temp reading and one person not stirring?

[Frankenbrew]

All great answers.

I usually heat my strike water to about 15 degrees higher than mash temp, and if it is cold outside, I'll either wrap the mash tun in a sleeping bag or take it inside the house. Experience has taught me to go hotter and cool with ice cubes, (a technique I learned here from Denny Conn) and then close her up for the entire mash time. If you follow a regular regimen you can measure temperature at the end of the mash, before your run-off, and note your heat loss, you can compensate by starting a bit hotter and then shooting for an average mash temperature. You may also want to figure that a higher mash temperature will result in a quicker conversion and conversely a lower mash temperature a longer conversion time and adjust your averages accordingly.

The great thing about brewing is that it provides you with plenty of intellectual stimulation. Brew, learn, adjust, repeat. Welcome to the obsession. There are many things you can become mesmerized or obsessed with these days, of which brewing is not even close to the worst.

[duboman]

I pre-heated the mashtun by pouring boiling water in it and letting it sit for a few minutes. I then poured out the water before mashing in. When I mashed in, I stirred until there were no dry or clumpy grain. I closed the mashtun and opened it about once every ten minutes to take a temperature reading. I will most definitely try the blanket idea and also not opening the mashtun as often. @duboman - what do you mean by "thermometer is properly calibrated."?

Basically your thermometer should read 212 at boiling and 32 at freezing just like your hydrometer should read 1.000 in plain 68oF water. If you can verify actual mash temps as well its a bonus.

If your measuring devices are off then you need to account for the differences on your actual readings.

Sent from my SAMSUNG-SM-G920A using Tapatalk

[Stevie]

Many (most?) hydrometers are calibrated at 60°