double boiler: what I don't understand...

In our view 30 gallons and under is considered hobby size. Do not bring anything larger than this to our site.

Moderator: Site Moderator

Post Reply
User avatar
Fredistiller
Site Donor
Site Donor
Posts: 253
Joined: Fri Feb 07, 2014 11:48 am
Location: Somewhere in Europe

double boiler: what I don't understand...

Post by Fredistiller »

Hello everybody!

I plan making a double boiler (my other topic :http://homedistiller.org/forum/viewtopi ... 3#p7400903 ) This is a specific question about the boiler so a made a new topic here.

What I don't understand is :" why is water worst than glycol/oil". IF my boiler is wel insulated, then I should not have to go above 100°C. So no evaporation. Water is safe, cheap, and not messy. Ideal I think...

BUT I read posts of much more experienced people than me, and they almost praise glycol/oil. Far from me the idea that I am smarter! I just don't understand or find my answer in what I am reading.

Could someone (simply) explain this to me please?
User avatar
pfshine
Site Donor
Site Donor
Posts: 3106
Joined: Thu Jan 19, 2012 10:59 pm
Location: Vegas

Re: double boiler: what I don't understand...

Post by pfshine »

It's a better heat transfer medium and won't make steam to go boom.
Life is a journey you take alone. Make sure you do what you what makes you happy
User avatar
MichiganCornhusker
retired
Posts: 4527
Joined: Mon Jun 23, 2014 9:24 am

Re: double boiler: what I don't understand...

Post by MichiganCornhusker »

Oil or glycol can be heated to higher temps before boiling than water.

Having a greater difference in temps makes a double boiler work better, but you can do it with water, too.

Check out this thread: http://homedistiller.org/forum/viewtopi ... 83&t=59138
Shouting and shooting, I can't let them catch me...
User avatar
DAD300
Master of Distillation
Posts: 2839
Joined: Wed Mar 02, 2011 11:46 am
Location: Southern U.S.

Re: double boiler: what I don't understand...

Post by DAD300 »

a water bath with an open vent is pretty safe. There are those that purposely use water in a slightly dif way.

They only fill the water bath half way and use it as a self contained steam generator. This takes more vigilance, better safety reliefs and more vigilance. stutter on the vigilance...

If I were running regularly, I'd spend the dollars for oil. The glycol scares me...
CCVM http://homedistiller.org/forum/viewtopi ... d#p7104768" onclick="window.open(this.href);return false;" rel="nofollow
Ethyl Carbamate Docs viewtopic.php?f=6&t=55219&p=7309262&hil ... e#p7309262
DSP-AR-20005
User avatar
Yummyrum
Global moderator
Posts: 7653
Joined: Sat Jul 06, 2013 2:23 am
Location: Fraser Coast QLD Aussie

Re: double boiler: what I don't understand...

Post by Yummyrum »

Does glycol or oil expand as it i heated ?
vqstatesman
Swill Maker
Posts: 185
Joined: Mon Jun 06, 2016 1:58 am
Location: South Australia

Re: double boiler: what I don't understand...

Post by vqstatesman »

Yummyrum wrote:Does glycol or oil expand as it i heated ?
I'm curious to know if glycol expands too. Any comments guys?
User avatar
shadylane
Master of Distillation
Posts: 10363
Joined: Sat Oct 27, 2007 11:54 pm
Location: Hiding In the Boiler room of the Insane asylum

Re: double boiler: what I don't understand...

Post by shadylane »

http://www.engineeringtoolbox.com/cubic ... _1262.html" onclick="window.open(this.href);return false;" rel="nofollow
User avatar
BDF
Swill Maker
Posts: 249
Joined: Sun Dec 30, 2012 7:38 pm
Location: USA Midwest

Re: double boiler: what I don't understand...

Post by BDF »

The speed of the boil on the inside is determined by how large of a temperature diff there is between the stuff inside and outside.

Sure you can bring a pot to boil on your stovetop on low frame, but it'll take freaking forever and won't ever boil as hard as having it on high.
User avatar
Brutal
Site Donor
Site Donor
Posts: 1349
Joined: Sat May 18, 2013 6:02 pm

Re: double boiler: what I don't understand...

Post by Brutal »

Glycol expands.. That's why your car radiator has 15 psi in it.

This is the deal with water in a double boiler. The heat energy is transmitted to your wash/mash through contact area and temperature differential (difference.) If there is a large difference in temp the heat will transfer quickly, and conversely if the temp difference is small it will transfer much slower. With water in the jacket you are limited to 212f unless you want to run pressure in your jacket. Many here would not run pressure in the jacket. It contains a lot of stored energy and a failure can be catastrophic. If you run glycol or oil in the jacket you can heat either one to a higher temperature than water. With a jacket of oil at 250-300f heat energy will be transmitted to your wash/mash much faster and with no pressure in the jacket. Yes oil/glycol will expand but a simple vent tube will prevent pressure build up. Oil and glycol also can be left in the jacket with no worry of bacteria going crazy in there, and neither will freeze and break out of the jacket if they get cold.
Steam injection rig http://tinyurl.com/kxmz8hy
All grain corn mash with steam injection and enzymes http://tinyurl.com/mp6zdt5
Inner tube condenser http://tinyurl.com/zkp3ps6
Post Reply