Crown Or Birko Urns - Extra Element Installation?

[crundle]

Good point about the power supply tripping out guys, I have organised to run a thick extension lead from another circuit to power the immersion element.

My plan is to use the thermostat controlled element to reach mashing temperature and to raise up to mashout, then with the grain bag removed, to turn off the thermostat controlled element and to boil using the immersion element only. This should address the main issue I am having, of the rolling boil just starting then being switched off. 2400W should be plenty to get a good rolling boil, so 1 element should be enough. i think if I tried to run both, that the thermostat controlled one wouldn't do much work anyway, because the temperature of boiling water would cut power to it.

Crundle

 

[Bribie G]

I think I found some extra power

QldKev

Apollo 13 this is Houston, we have found that extra power for you, now here's the re-entry plan.........

ok it's obviously time to get off my bum and do some brewing.

 

[crundle]

Well, I have just brewed my first beer since getting a camping mat for the Crown, and also gave the 4108B immersion element a crack - wow!

Was brewing outside and it got a great boil going, even without the immersion element. I had both going to get it boiling faster, but had to disconnect the immersion element or it would have boiled over the sides. Once the level had gone down a touch, I used both and was getting an evaporation rate of about 17%/hour.

It cost me $10 for the camping mat, and $82.50 for the element, so a nice cheap way to upgrade the urn.

Can anyone tell me what the maximum volume of wort that can be reasonably boiled with a single 2400W element? Just thinking ahead if I ever have the need to upgrade to do double batches, what the largest boiler size could be.....

Pics of the brewday










Crundle

 

[muckanic]

Can anyone tell me what the maximum volume of wort that can be reasonably boiled with a single 2400W element? Just thinking ahead if I ever have the need to upgrade to do double batches, what the largest boiler size could be.....

About 35L uninsulated, with double batches possible with appropriate insulation and maybe partial lid on depending upon ambient conditions. Starting off with hot tap water makes life a heck of a lot easier.

Still getting my head around this notion of "tapping into" the oven or HWS circuits. :blink:

 

[smollocks]

crundle can you tell me where you found the camping mat? I've tried GoLo (no luck) and Clark Rubber only had yoga mats for $80 or thinner mats for about $20-$25.

It seems that the Crown is getting a reputation here for being underpowered, but my experience doesn't entirely support that. Here's my data, for what it's worth. My first BIAB brew in the Crown I did get periodic pauses in boiling as the thermostat shut off the element. It only happened toward the end of the boil and I got 6.7% evaporation as a result.

My theory was that the shutoffs were caused by the thermostat getting coated with a film of hardened wort. This causes a higher local temperature at the thermostat than in the bulk wort, and it thinks it can hold back on the boil. Alternatively, too much hardened wort on the element might cause the element to overheat and shut off to prevent a fault.

To try and prevent this, I sat a cake stand over the element & thermostat before the mash to keep the bag and grain from settling on top of them. After removing the bag I also gave the element a few scrapes with a spoon to remove any wort that might have settled on the element but not yet hardened. This is not scientific proof, but in the 2 brews since doing this I've not seen the problem recur despite increasing my boil to 80 minutes. I brew inside but next to a door open to the outside, with a fan blowing the steam out the door. The boil has been vigorous and continuous, with evaporation rates of 13% and 11%.

So far I'm quite happy with the Crown urn.

 

[smollocks]

And maybe this is just me, but I don't see why everyone believes winter weather would cause the urn to boil less. I would have thought that colder ambient temperatures would cause greater heat loss to the environment, making it harder for the urn to reach boiling point, and therefore causing it to boil longer & harder.

 

[captaincleanoff]

I would have thought that colder ambient temperatures would cause greater heat loss to the environment, making it harder for the urn to reach boiling point, and therefore causing it to boil longer & harder.

:unsure:

 

[Wolfy]

And maybe this is just me, but I don't see why everyone believes winter weather would cause the urn to boil less. I would have thought that colder ambient temperatures would cause greater heat loss to the environment, making it harder for the urn to reach boiling point, and therefore causing it to boil longer & harder.

With colder ambient temps and more heat loss, the urn has to put in more energy to get the liquid to boil.
If the urn was already struggling to get a decent boil going, it will be worse with colder ambient temp due to the additional heat loss - that's why it's called heat loss, the heat is lost to the environment rather than going into making your liquid boil.
If you insulate the urn those losses and the ambient temp should be mostly irrelevant.

 

[flattop]

I get a boil on my Crown but i have to admit it doesn't hit 100*c it hovers around 95* with the lid off. I haven't been using my campers mat while i boil inside as there is no crosswind unlike my balcony, but i had a 120 min boil yesterday and still didn't hit my numbers as well as i would like so i think next brew the campers mat goes back on.

For those who asked, Reject shop and Aussie disposals sell cheap ones.

 

[smollocks]

With colder ambient temps and more heat loss, the urn has to put in more energy to get the liquid to boil.
If the urn was already struggling to get a decent boil going, it will be worse with colder ambient temp due to the additional heat loss - that's why it's called heat loss, the heat is lost to the environment rather than going into making your liquid boil.
If you insulate the urn those losses and the ambient temp should be mostly irrelevant.

Agreed, but from my understanding it's not that the urn is going full-bore non-stop and still cannot reach a boil. The issue is that it's reaching a boil, and then cutting out intermittently. To me it acted more as if the thermostat reached the set temperature and then switched off. Happy to be corrected if that's not others' experience, but it is mine.

 

[flattop]

I think your point is relevant, the crown does cycle power. I wonder if it is the trub, creating a blanket of insulation over the temp probe.
I don't agree that the probe is getting a baked on cake of crud, mine always seems clean enough when i clean the urn.
Important to note though that the heat source is at the bottom of the urn and we measure temp at the top, i know heat rises but the wort is thicker than water and it's possible the trub is creating hot spots causing the urn to cycle. I guess a false bottom would assist in reducing that, it would be nice to have a trub bucket at the bottom below the element!

 

[Wolfy]

Agreed, but from my understanding it's not that the urn is going full-bore non-stop and still cannot reach a boil. The issue is that it's reaching a boil, and then cutting out intermittently. To me it acted more as if the thermostat reached the set temperature and then switched off. Happy to be corrected if that's not others' experience, but it is mine.

Ahh fair enough, I did not think of that, my (Roband?) urn has a dial with markings up to 120deg, so I just crank it all the way up and have no problems.

 

[crundle]

The Crown has markings up to 110 degrees, but just from experience it performs worse in the cold than in the warmer months.

I got the camping mat from Kmart at Collonades shopping centre for $10. It makes a real difference to the vigor of the boil, but I only have data based on the following.

With no mat or extra element, I was getting 7.6% per hour boil off (warmer weather)
with the mat and extra element I am getting about 17% per hour (cold weather) - I am thinking that the extra element, keeping the water boiling, actually left very little work for the internal element to do.

It would be interesting to see what difference the mat alone makes, maybe something to try for my next brew, but I did see a difference in boil vigor with the mat and the Crown internal element going prior to using the immersion, but didn't get a chance to measure it objectively. I guess that there is some correlation between weather and boil rate, I will have to google that one.

Crundle

 

[nvs-brews]

anyone know what watt is in a 20L birko?