Brewtroller Build Part Three - Electric Heating Elements

[Reuben Rowntree]

I decided to go for 3kW elements, it seems that would be about the biggest I could go for without requiring new switches and fuses in my house. My circuit breaker is rated to 20A, and as a good rule of thumb I'm going to try and keep this below 15A. Basically, the bigger the element, the quicker I can heat the water to start the mash and get the boil rolling.

 

The Maths:

20A x 230V = 4600W (max)

15A x 230V = 3450W (my target)

 

Therefore: 3000W/230V = 13A

I have some pumps and relays that could draw up to 1A or so but all up I should be less than 15A I think.

 

I bought the elements from Bunnings Warehouse for about $60 each. These guys were by far the cheapest that I found and I'd heard of the brand so I think they will be pretty sweet - Hermatic I think it was called.

 

I bought the junction boxes from Jaycar Electronics here.

 

 

Sealiing:

Sealing the element took a couple of attempts, I couldn't seal it from the outside like I had with the valves, so this time I had a silicone rubber O-ring on the inside. However it wouldn't seal on it's own, so I added a few twists of thread tape to seal the backnut against the thread, and the O-ring actually seals quite nicely against the wall of the pot and the backnut.

 

Drilling Holes:

Drilling the holes was a major hassle, I used my trusty step drill as shown in a previous post, but the max size is 39mm and I needed about 43mm so I had quite a bit of filing to do. Pretty much zero fun, but at least it didn't cost me anything. Next time I would consider buying a chassis punch, I actually looked into hiring one, but nobody had the right size.

 

Finished Images:

Links to all posts in this series:

http://www.forum.realbeer.co.nz/profiles/blogs/brewtroller-system-b...

http://www.forum.realbeer.co.nz/profiles/blogs/brewtroller-build-ma...

http://www.forum.realbeer.co.nz/profiles/blogs/brewtroller-build-pa...

http://www.forum.realbeer.co.nz/profiles/blogs/brewtroller-build-pa...

http://www.forum.realbeer.co.nz/profiles/blogs/brewtroller-build-pa...

 

Update 1: I was getting thirsty (and low on beer) so I had to brew a batch of beer this week - a Kolsch by the way. I wanted to give the electric heater a whirl so I heated up the water in my BK - basically using it as a HLT. It took about 25min to heat 30L to 72ºC - not bad I reckon.

[martin w]

if its not already too late you should consider gas for the bk, i have a 3kw element in mine and i'm going to get rid of it and convert to gas, if i do a 45 liter boil it never really gets vigorous, and i put down my recent bouts of dms to this, the element also means you can't do a decent whirlpool to form a trub cone in the middle of the kettle.

[Barry]

I get a decent trub cone whirlpooling with an electric kettle.

I agree with the 45l boil though, you'll need the lid partly on to get a vigorous boil of 45l with a 3kw element.

I leave the kettle partly covered until the last 15 minutes, haven't had DMS issues that I've been aware of.

[martin w]

whats you technique for getting a decent cone? all i get is a watery pile of sludge and i end up losing a couple of litres of wort to it!

[Barry]

Using a big spoon I just stir as fast as I can. The technique involves lifting the spoon above the element with each swirl, sounds like a pain in the arse but I find it pretty successful.

[Reuben Rowntree]

Yeah, it sounds like 3kW is a little under powered - I actually thought it would be heaps given that some people are using 2kW - but that is obviously for much smaller batches. I'm going to insulate the kettle with a Pink Batts hot water cylinder wrap or something similar, and hopefully this will keep it warm enough so I don't have to leave the lid half on. Is your kettle insulated Martin?

I've got a 3-ring gas burner as well so I might end up using both, and dialing back the electricity with the BrewTroller to keep the boil going. Would be nice to avoid the burner though :)

[martin w]

its uninsulated, i have thought about insulating it, i've wrapped blankets and a sleeping bag around it in the past but it didn't make a huge difference, i also thought about a 'chimney lid' like those you see in old style copper breweries,but thats never progressed to more than a thought so far.

[Vesku]

Looking good!

I'm tempted to try a electric kettle made in a chilly bin. Anyone know how much toxic chemicals come of from plastics?!? I've noticed in my HERMS that the chilly bin I've been using for the heat exchanger is suffering a bit and I'm only up to 80C temperatures max., the plastic has changed it's form etc. So, maybe it's better to use ss pot and insulate that :P

I wouldn't want Pink Batts anywhere near my brews, what else is available? I know that there's a lot of products for insulating car hoods etc. Anyone know are these products available here in NZ? Something like this: http://www.jl-joustoliitin.fi/index.php?id=60 (up to 1000C)