Heating element question - sizing

[rkhanso]

I just picked up a 26gal aluminum kettle and wanted to put in an electric element to use with my Craftbeerpi controller. Planning on doing BIAB, having an electric element in the kettle with a small pump circulating the wort to help keep temp stratification at a minimum and Craftbeerpi controlling the mash temp. I made a counter-flow chiller so since I have the pump for that, I thought it might be OK to use it to recirculate wort during mashing also.

I plan on making 10 gallon batches to start with. Maybe 5 gallons occasionally if the pot isn't too large for that. The kettle is about 17.5" tall and 20.5" in diameter. It's heavy-duty at 1/4" thick.

I'm wondering if I need two 5500W elements, or maybe a combination of 5500W and a smaller size, say 1500W. (The Dernord elements on Amazon)

I used the calculator on this website http://manskirtbrewing.com/calculators.aspx and notice that the times aren't too different when figuring 10 gallons of water. With less volumes, the time differences are even less noticeable. It's not until you get 20 gallons or so when the times really stretch out with the lower wattages.

But....I've not yet used the BIAB method and don't know if I'll really want a certain amount of wattage.

Or, am I way off track?

Opinions?

 

[doug293cz]

Doesn't sound like that pot would be good for 5 gal batches. Your end of boil volume would be about 5.5 gal, and that would only have a depth of 3.85" in such a wide kettle. Depending on how the elements are mounted, it might not be enough to cover them.

Brew on

 

[rkhanso]

OK. I didn't think of checking the depth for just a 5 gal batch...
I'll have to up the minimum size then for BIAB - and if I want to make only 5gal, I'll keep doing extract kits in my 5 gallon kettle.

About the heat element sizing....

Using the manskirtbrewing calculator and heating 11 gallons:

5500W - heating 45F to 155F will take 34 minutes
heating 155F to boiling will take 17.5 minutes

6000W - heating 45F to 155F will take 31 minutes
heating 155F to boiling will take 16.1 minutes

7000W - heating 45F to 155F will take 26.63 minutes
heating 155F to boiling will take 13.8 minutes

11000W - heating 45F to 155F will take 17 minutes
heating 155F to boiling will take 8.78 minutes

I suppose this is all a subjective thing, each person having a personal preference. I have nothing to go on since I've not brewed BIAB before.
Opinions?

 

[doug293cz]

Basically you're going to trade off cost vs. heating time. To get more than 5500W you're going to need multiple elements (even if you can get larger elements, you probably don't want to use those due to high watt density), larger gauge (costlier) wire, more complexity in the control panel, more expensive GFCI, etc. How much do you want to invest in a low end Al kettle? A single element 5500W system can be done pretty cheaply.

Brew on

 

[rkhanso]

I guess I can always add more elements later if needed. I'll start out with a single 5500W element. If needed, I can add a 2000W/120v for a little extra boost during getting up to temp.

On a side note......I've been testing my fermentation control and it's looking pretty good. Getting only a .22F fluctuation (after the initial warm-up and cool-down problem. This was only a test).