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General Category => All Grain Brewing => Topic started by: hiphophead on January 15, 2011, 04:41:43 PM

Title: heatstick/heat exchange
Post by: hiphophead on January 15, 2011, 04:41:43 PM
im thinking of purchasing this 3/4 in stainless immertion header for my heatsick construction for my RIMS.  what do you think. i was gunna put the heat sensor on the output back into the keg.  its a johnson controls one from northern brewer but it has a 2 degree fudge factor. wont kick on untill it drops 2 degrees.  is there a beeter one out there that shows current temp and set temp on the same screen.

http://www.omega.com/ppt/pptsc.asp?ref=EMH_Heater (http://www.omega.com/ppt/pptsc.asp?ref=EMH_Heater)
Title: Re: heatstick/heat exchange
Post by: a10t2 on January 15, 2011, 05:28:58 PM
Is that 2°F? As a practical consideration, I wouldn't worry about variations smaller than that. If precision is a serious concern, though, the Ranco ETC series will let you set a 1°F differential.

I don't think you'll be happy with a 500 W element either, unless all you're using it for is to maintain temps. That will only raise the temperature of a typical mash (10 lb grain, 4 gal water) by 1°F every 1.3 minutes - assuming no losses. Doing a step mash would be pretty impractical.

$70 (or really, $141) for an element seems pretty pricey. It's nice that they're sealed and all, but I'd still go with the $15 one from the hardware store. I'm a tightwad though.
Title: Re: heatstick/heat exchange
Post by: hiphophead on January 15, 2011, 06:21:50 PM
what about this PID instead of my johnson controls one.  even though i already own the A419 i can just use thatone in my fermentaion chamber.  but this is one that i dream of and it only 45 bucks.  but is it better?
http://www.auberins.com/index.php?main_page=product_info&products_id=106 (http://www.auberins.com/index.php?main_page=product_info&products_id=106)
Title: Re: heatstick/heat exchange
Post by: dak0415 on January 16, 2011, 03:11:58 AM
This one is better for a RIMS.


add a 40 amp SSR


with a low watt density 4500 watt 240v water heater element at 120v
Title: Re: heatstick/heat exchange
Post by: a10t2 on January 16, 2011, 03:28:58 AM
I don't know anything about commercial PID units, but as a control algorithm I have to think it's overkill for this application. Unless you're going to set up a PWM setup, there's no point using anything other than a basic, linear, thermostat-type controller. Using your 2°F differential, set the target 1°F higher than your desired temp, get a 1-2 kW element and a relay for it to control, and you'll be in business. That's the basic setup we use for temperature control in our 7 bbl brewhouse, and it's all you need.