Get your HBT Growlers, Shirts and Membership before the Rush!


Home Brew Forums > Home Brewing Beer > Equipment/Sanitation > Controlling a boil with a PID
Reply
 
LinkBack Thread Tools
Old 05-09-2008, 05:42 PM   #1
bgrubb7
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2007
Location: Effingham, IL
Posts: 137
Liked 1 Times on 1 Posts

Default Controlling a boil with a PID

I have read a lot of posts talking about operating an Electric Boil kettle using a PID in manual mode by adjusting the duty cycle up or down to control a boil. Why can't you just set the temp at 212 or a little higher, and let the PID do the work?

__________________
bgrubb7 is offline
 
Reply With Quote Quick reply to this message
Old 05-09-2008, 05:48 PM   #2
mr x
Feedback Score: 0 reviews
Recipes 
 
Join Date: May 2007
Location: Mainly Halifax
Posts: 1,589
Liked 3 Times on 3 Posts

Default

If you set it over 212 in an mlt, it will never shut off. Setting to manual and picking an output once you know your equipment is a better way to go if you want to boil.

That should read 'If you set it over the boiling point...'

__________________

This place really went to hell. Follow the OF standard stout. Bye.


mr x is offline
 
Reply With Quote Quick reply to this message
Old 05-09-2008, 06:28 PM   #3
lustreking
Feedback Score: 0 reviews
Recipes 
 
Join Date: Aug 2006
Location: Bethlehem, PA
Posts: 750
Liked 18 Times on 17 Posts
Likes Given: 7

Default

Boiling is boiling. You can't control the temperature of a boil, simmer to full-rolling should be the same temperature. What you want to control is the rate of the boil.

__________________

My brewing site:
http://brewing.lustreking.com

lustreking is offline
 
Reply With Quote Quick reply to this message
Old 05-11-2008, 02:01 AM   #4
bgrubb7
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2007
Location: Effingham, IL
Posts: 137
Liked 1 Times on 1 Posts

Default

That's sort of what I originally thought. A boil physically cannot be hotter than 212. Then why do I get different results with my analog thermo? At a 212 reading, I have a gentle boil, but I can crank my flame up for a vigorous boil, and then get a 215 to 220 reading. I do calibrate my thermo to ice water before I brew. Is my thermo just not accurate or am I missing something here?

__________________
bgrubb7 is offline
 
Reply With Quote Quick reply to this message
Old 05-11-2008, 02:16 AM   #5
littlehop
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2008
Location: Port Townsend Wash.
Posts: 65
Default

You're not brewing in death valley are you?
__________________

littlehop trys to make enough
but it keeps getting druck

littlehop is offline
 
Reply With Quote Quick reply to this message
Old 05-11-2008, 04:08 AM   #6
Bobby_M
Vendor and Brewer
HBT_SPONSOR.png
Vendor Ads 
Feedback Score: 2 reviews
 
Bobby_M's Avatar
Recipes 
 
Join Date: Aug 2006
Location: Whitehouse Station, NJ
Posts: 22,282
Liked 1073 Times on 716 Posts
Likes Given: 28

Default

I suspect maybe your thermo is reading 3 degrees too high.

__________________
BrewHardware.com has a new website. Please check it out and let me know what you think!
New 100% Stainless Steel Heating Elements are IN!
Chugger Pumps, Pump Kits, Camlocks, Sightglasses, Clear USA made Silicone Tubing, RIMS, Electric Install Parts, etc. Did you know we are also now a full service homebrew shop selling malt, hops, yeast (Wyeast), etc?
Bobby_M is offline
 
Reply With Quote Quick reply to this message
Old 05-11-2008, 09:30 AM   #7
mr x
Feedback Score: 0 reviews
Recipes 
 
Join Date: May 2007
Location: Mainly Halifax
Posts: 1,589
Liked 3 Times on 3 Posts

Default

Quote:
Originally Posted by bgrubb7 View Post
That's sort of what I originally thought. A boil physically cannot be hotter than 212.
You're talking about pure H20 at sea level air pressure(1 atmosphere). Anything else will yield different numbers.
__________________

This place really went to hell. Follow the OF standard stout. Bye.

mr x 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
Controlling fermentation temps nasmeyer Beginners Beer Brewing Forum 11 03-10-2009 11:28 PM
Controlling Sweetness JohnBarleycornATL Beginners Beer Brewing Forum 2 01-29-2009 03:07 PM
controlling fermentation temperature THEDIETZ General Techniques 8 11-12-2008 10:08 PM
Controlling heater elements AiredAle Equipment/Sanitation 20 01-10-2007 03:21 AM
Controlling the temperature Beer is good All Grain & Partial Mash Brewing 12 08-31-2006 08:07 AM



Newest Threads

LATEST SPONSOR DEALS