Kegconnection Complete Starter Kit and More Giveaway!


Home Brew Forums > Home Brewing Beer > Beginners Beer Brewing Forum > How many BTU's need to boil 3 gallons?

Reply
 
LinkBack Thread Tools
Old 03-03-2013, 11:28 PM   #1
poppafritz
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2013
Location: Gig Harbor, WA
Posts: 22
Likes Given: 7

Default How many BTU's need to boil 3 gallons?

So i am looking into getting a propane burner to do my wort in because after my first batch i learned that my stove top is not up to the challenge. Looking around and doing some math i have learned a few things. I wanted to double check my math with you all and see if i am doing this right.

My tap water comes out at 55° and water boils at 212°.
1 gal. of water weighs 8.3 lbs
Weight X Differences of Water temp to boil temp = BTU per gal
8.3 x (212 - 55) = 1303.1 BTU's to boil 1 gal.

If i am boiling 2.5 gals of water then i will need a burner with a BTU rating of 3257.75 BTU's to boil my pot. Now this math is with the idea of 100% heat transfer from source to water, this number is not quite right. Under the right conditions were looking at more like 75% to 80% so that bumps up our BTU's to roughly 3909.3 or rounded to 4k BTU's

With that said... these two burners should be more then enough right?

http://www.amazon.com/Cajun-Cookware-Outdoor-Burner-Pressure/dp/B0000E2VR4/ref=sr_1_52?s=lawn-garden&ie=UTF8&qid=1362355196&sr=1-52&keywords=turkey+fryer

http://www.amazon.com/Bayou-Classic-SP1-Jet-Cooker/dp/B0002913MI/ref=sr_1_67?s=lawn-garden&ie=UTF8&qid=1362355196&sr=1-67&keywords=turkey+fryer

__________________
poppafritz is offline
 
Reply With Quote Quick reply to this message
Old 03-03-2013, 11:46 PM   #2
theveganbrewer
Feedback Score: 1 reviews
Recipes 
 
Join Date: Sep 2011
Location: Beaverton, OR
Posts: 1,937
Liked 290 Times on 206 Posts
Likes Given: 265

Default

Bayou Classic SP10 or the SQ14 will both work. I see the SP1 is pretty cheap, will also do the job easily.

__________________

-Retired Homebrewer

theveganbrewer is offline
 
Reply With Quote Quick reply to this message
Old 03-04-2013, 12:31 AM   #3
BlackDogBrew
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2013
Location: , Michigan
Posts: 26
Liked 1 Times on 1 Posts

Default

This Walmart Turkey Fryer works well. Comes with Burner, regulator, hose and a 30 qt alum pot. My local Walmart had it in stock, even though it says out of stock online. Check the ship to store or local store inventory checker.

I used it for my 3 gal extract brews. Easy to bring to temp, and easy to hold from boil overs.

__________________
BlackDogBrew is offline
 
Reply With Quote Quick reply to this message
Old 03-04-2013, 01:01 AM   #4
poppafritz
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2013
Location: Gig Harbor, WA
Posts: 22
Likes Given: 7

Default

Thanks guys i think i have a much better idea of what im looking for now.

__________________
poppafritz is offline
 
Reply With Quote Quick reply to this message
Old 03-04-2013, 03:10 AM   #5
VladOfTrub
Feedback Score: 0 reviews
Recipes 
 
Join Date: Oct 2011
Location: , Pa
Posts: 549
Liked 96 Times on 71 Posts
Likes Given: 123

Default

The formula doesn't take into consideration change of state. The 1lb 1 degree = 1 BTU doesn't apply during change of state (boiling). Add another 960 BTU/Hr per lb. to change state, add to that number the BTU for TD. It takes a lot of energy to change state. So, you'll need about 20K BTU/Hr to change state and another 4K BTU/Hr for TD = 24K BTU/Hr. The Cajun is slightly undersized at 20K BTU/Hr. Unless, it can be throttled way down, the 185K at 20 PSI is over kill for boiling 2.5 gallons. Either burner will work. However, thay may not be the best choice for your process. Camp Chef makes a 30K and a 60K that can be throttled down. The Blichmann is 72K at 10 PSI and can be throttled down.

__________________
VladOfTrub is offline
 
Reply With Quote Quick reply to this message
Old 03-04-2013, 03:14 AM   #6
thargrav
Registered User
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2009
Location: Huntsville, Alabama
Posts: 821
Liked 38 Times on 35 Posts
Likes Given: 2

Default

Quote:
Originally Posted by poppafritz View Post
So i am looking into getting a propane burner to do my wort in because after my first batch i learned that my stove top is not up to the challenge. Looking around and doing some math i have learned a few things. I wanted to double check my math with you all and see if i am doing this right.

My tap water comes out at 55° and water boils at 212°.
1 gal. of water weighs 8.3 lbs
Weight X Differences of Water temp to boil temp = BTU per gal
8.3 x (212 - 55) = 1303.1 BTU's to boil 1 gal.

If i am boiling 2.5 gals of water then i will need a burner with a BTU rating of 3257.75 BTU's to boil my pot. Now this math is with the idea of 100% heat transfer from source to water, this number is not quite right. Under the right conditions were looking at more like 75% to 80% so that bumps up our BTU's to roughly 3909.3 or rounded to 4k BTU's

With that said... these two burners should be more then enough right?

http://www.amazon.com/Cajun-Cookware-Outdoor-Burner-Pressure/dp/B0000E2VR4/ref=sr_1_52?s=lawn-garden&ie=UTF8&qid=1362355196&sr=1-52&keywords=turkey+fryer

http://www.amazon.com/Bayou-Classic-SP1-Jet-Cooker/dp/B0002913MI/ref=sr_1_67?s=lawn-garden&ie=UTF8&qid=1362355196&sr=1-67&keywords=turkey+fryer
At best a open flame on the bottom of your pot is 50% efficient but your efficiency could easily drop to 25% during a windy or cold day.
__________________
thargrav is offline
 
Reply With Quote Quick reply to this message
Old 03-04-2013, 03:16 AM   #7
thargrav
Registered User
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2009
Location: Huntsville, Alabama
Posts: 821
Liked 38 Times on 35 Posts
Likes Given: 2

Default

Quote:
Originally Posted by VladOfTrub View Post
The formula doesn't take into consideration change of state. The 1lb 1 degree = 1 BTU doesn't apply during change of state (boiling). Add another 960 BTU/Hr per lb. to change state, add to that number the BTU for TD. It takes a lot of energy to change state. So, you'll need about 20K BTU/Hr to change state and another 4K BTU/Hr for TD = 24K BTU/Hr. The Cajun is slightly undersized at 20K BTU/Hr. Unless, it can be throttled way down, the 185K at 20 PSI is over kill for boiling 2.5 gallons. Either burner will work. However, thay may not be the best choice for your process. Camp Chef makes a 30K and a 60K that can be throttled down. The Blichmann is 72K at 10 PSI and can be throttled down.
The conversion for boil-off is 8000 BTU per gallon, before factoring in inefficiencies. And gas fired is about 50% efficient at best.
__________________
thargrav is offline
 
Reply With Quote Quick reply to this message
Old 03-04-2013, 04:09 AM   #8
OrdinaryAvgGuy
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2013
Location: Cary, NC - North Carolina
Posts: 958
Liked 180 Times on 127 Posts
Likes Given: 104

Default

Quote:
Originally Posted by theveganbrewer View Post
Bayou Classic SP10 or the SQ14 will both work. I see the SP1 is pretty cheap, will also do the job easily.
For 3 gallons I would skip the math and go with this.

+1 on the SQ14. Got mine on Amazon for less than $50 shipped.
__________________
Primary: -
Bottled: X-mas ale, Southern Tier Pumking Ale, Sierra Nevada Torpedo Clone
OrdinaryAvgGuy is offline
 
Reply With Quote Quick reply to this message
Old 03-06-2013, 11:47 PM   #9
poppafritz
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2013
Location: Gig Harbor, WA
Posts: 22
Likes Given: 7

Default

Thanks guys ill look into some of the other options here.

__________________
poppafritz is offline
 
Reply With Quote Quick reply to this message
Reply


Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
How many points of gravity should i get when i boil 8.75 gallons down to 6 gallons? pmcquillen Brew Science 7 08-07-2012 07:14 PM
brewing ten gallons with 6 gallons boil pot 400d All Grain & Partial Mash Brewing 17 03-12-2011 02:24 PM
Gallons per boil ETOHonboard Extract Brewing 6 03-08-2011 06:54 PM
Can I boil just under 5 gallons? joeunc All Grain & Partial Mash Brewing 11 11-16-2010 02:33 AM
Getting 12 gallons up to boil tkone DIY Projects 10 07-09-2009 12:43 PM