E-keggle Won't Maintain Boil

[iralosavic]

I'm just doing some calculations (time to mash-in, time to boil, evaporation rate etc) on my keggle, which I've just fitted with a 2200w weldless element.

For my test run I started with 35L of 19c water. With the lid on, it reached a rolling boil after an hour and a half. About 10 minutes (wasn't monitoring closely) after removing the lid, the boil dropped back to around 96c where it struggled to surpass for the remainder of a 60 minute "boil".

Couple of questions.

1. Is my element simply underpowered or am I going to be able to fix this problem by insulating the sidewalls of the keggle better? (It already has a few layers of insulating tape, but you can still clearly feel the heat through the walls as though it does next to nothing.)


2. Will the difference bewteen 96c and 100c for 60 minutes make a measurable (in practical proportions) difference to evaporation rate?



Cheers

 

[mxd]

when I started I had a 2200 w element and couldn't get to a boil even with a lid on and insulation, so I run 2 elements (over the side 2400 w and a 2200 w), I know guys with the urns 2400W can do a rolling boil no lid and good insulation.

What you can try is
1) place some foam or the like onto pf the wort whilst boiling or

2) a "temp lid" with a hole in the middle (i.e a smaller opening on the pot)

that till get you to a boil and still allow evaporation.

good luck

Matt

 

[kelbygreen]

Not using electric I cannot comment to much but in theory this sounds right.

1. better insulation will help keep the heat in, But if you are no chilling or have a plate chiller and the insulation is not removable then it will take longer for the convection to stop and longer till you can whirlpool and drain. Of coarse if using a immersion chiller this is not so much a problem but still might take longer to drop temps.

2. yes it will as 96c wont really be a rolling boil. it will evaporate and there should be convection still making the wort circulate. You need to aim for 10% boil off if you can get 10% boil off or more then I wouldnt worry about the temp. Also you will have to remember a wort is heavier then water and will need more heat to boil

 

[iralosavic]

when I started I had a 2200 w element and couldn't get to a boil even with a lid on and insulation, so I run 2 elements (over the side 2400 w and a 2200 w), I know guys with the urns 2400W can do a rolling boil no lid and good insulation.

What you can try is
1) place some foam or the like onto pf the wort whilst boiling or

2) a "temp lid" with a hole in the middle (i.e a smaller opening on the pot)

that till get you to a boil and still allow evaporation.

good luck

Matt

Thanks for your advice, Matt. I actually thought of a "partial lid", but mine is glass - so there's not much I can do with it. I may be able to make something out of stainless though. Hmm The whole reason to avoid leaving the lid on is to evaporate DMS... I wonder how effective this would be with a small hole in the centre to allow it to escape? Surely there'd be significant condensation trapped on the rest of the lid surface?


[quote post='889496' date='Mar 11 2012, 08:12 PM']Not using electric I cannot comment to much but in theory this sounds right.

1. better insulation will help keep the heat in, But if you are no chilling or have a plate chiller and the insulation is not removable then it will take longer for the convection to stop and longer till you can whirlpool and drain. Of coarse if using a immersion chiller this is not so much a problem but still might take longer to drop temps.

2. yes it will as 96c wont really be a rolling boil. it will evaporate and there should be convection still making the wort circulate. You need to aim for 10% boil off if you can get 10% boil off or more then I wouldnt worry about the temp. Also you will have to remember a wort is heavier then water and will need more heat to boil[/quote]


I'm not too concerned with a slightly longer wait before wirlpooling, although I would aim to use a removable insulation style anyway - something like a foam camping mat with cut-outs for taps etc strapped on with elastic straps. I guess it's worth a shot.

The temperature was taken as a guide for me to see how far off/underpowered it is. You're right, at 96c there were convection currents and gentle bubbling, but no signs of a boil. I got 8.6% evaporation in my test run. I'm guessing I'd be up at 10% if it were actually boiling for the whole time. Good point regarding the density of wort - although this makes me more nervous as I do not want to buy an immersion element (kind of defeats the purpose of trying to save money vs gas and may not be possible on the dodgey circuits in my house).

 

[kelbygreen]

if you have 2 power point circuits (like one for the house one for the shed) then you can run a lead off one of the circuits. Although depending on the length of the lead I would consult a electrician on what type of lead (if any) you can use. I would go a good quality one over a cheap one. As if its 2400w and you have to use say a 30m lead then I would def ask a professional first (and no one in bunnings is considered a professional) so ask on here there are plenty of electricians.

I thought of electricity but then only benifits I could see is cost of running them. Gas is faster and cheaper to set up and might cost more but the way electricity is going it might not be soon. I can heat 53lts of 68c wort up in 15mins and thats on about 3/4 power althought I turn it on just under 1/2 power while I am filling the kettle so does not take long once its filled.

 

[Online Brewing Supplies]

IMO you are not getting enough to feed your element, in my herms kettle unit I run 1 x 2.4 kw element (off of a15A circuit). It does take a while to get to the boil but once going its too much.
Run a test on how many amps you are pulling off the circuit. 2.4 / 240 = 10A, if your not getting that then your element is chocked.

Nev

 

[JaseH]

I managed a gentle rolling boil in my keggle with camp mat insulation and a 2200W element. I ended up using it for my HLT and a built a kettle using a 3600W element and get a good vigorous boil without insulation.

 

[kelbygreen]

Yeah but nev if he has a circuit breaker then it will trip out if its drawing to much. If its not cutting out and the wires are not suited for them amps then they can get very hot and melt. As I say you need to really watch out using electricity its not as simple as buying a big element and it will work you have to work with existing power in your house. I want to run 40amps to my shed will give me 2 x 15amp circuits and a 5-10 amp for my lights (will have to put a mini switch board in the shed) but If I want to I can run electricity then. ATM I have 15amp running the whole house power points and the shed is piggy backed off the house so if I run the dryer I cant put the kettle on or anything like that

 

[JaseH]

Yeah I run my rig on two circuits, I use a 10amp outlet for the HLT(2200w) and a 15amp circuit from the garage for the kettle.

 

[Online Brewing Supplies]

Yeah but nev if he has a circuit breaker then it will trip out if its drawing to much. If its not cutting out and the wires are not suited for them amps then they can get very hot and melt. As I say you need to really watch out using electricity its not as simple as buying a big element and it will work you have to work with existing power in your house. I want to run 40amps to my shed will give me 2 x 15amp circuits and a 5-10 amp for my lights (will have to put a mini switch board in the shed) but If I want to I can run electricity then. ATM I have 15amp running the whole house power points and the shed is piggy backed off the house so if I run the dryer I cant put the kettle on or anything like that

No circuit breaker = disaster.
Yep I see your point thats why I ran 440V (on BIG cable) to the brew cave, I still had problems tripping switches so I needed to break up the draw to different cable runs.
Now its sweet, coolroom , fridges, brew system all co exist without drop out.

Nev

 

[Online Brewing Supplies]

Yeah but nev if he has a circuit breaker then it will trip out if its drawing to much. If its not cutting out and the wires are not suited for them amps then they can get very hot and melt. As I say you need to really watch out using electricity its not as simple as buying a big element and it will work you have to work with existing power in your house. I want to run 40amps to my shed will give me 2 x 15amp circuits and a 5-10 amp for my lights (will have to put a mini switch board in the shed) but If I want to I can run electricity then. ATM I have 15amp running the whole house power points and the shed is piggy backed off the house so if I run the dryer I cant put the kettle on or anything like that

Also circuit breakers do get slack if tripped too many times, like a shock absorber thats had a hard life.
Some times just replacing that will stop it dropping out.
Nev

 

[Fat Bastard]

1. Is my element simply underpowered or am I going to be able to fix this problem by insulating the sidewalls of the keggle better? (It already has a few layers of insulating tape, but you can still clearly feel the heat through the walls as though it does next to nothing.)


Cheers

I run a 2400w element in my 36 litre kettle and it will boil the wort hard enough to have it jumping out of the pot at any volume over about 28 litres. It's pretty heavily insulated though.

I lived in a house a couple of years back where the fridge would struggle to hold 4 degrees, the stove never worked properly, and all my oil heaters would never get hot enough to heat the place in winter. My missus copped a shock one day from the tap and we called a lecco in to take a look and apparently the house was so badly wired that the outlets weren't supplying enough juice. One call to the power company got an emergency team out there to fix it up, because the lecco told them that my missus had got a shock, which made it an emergency. Apparently.

Might be worth getting a pro to check your power supply out.

 

[Sammus]

wow weird, I run a 1700W element with insulation and get a vigorous boil with no lid.. that said I have pretty wicked insulation using aeroflex. I heartily recommend it. In fact, I think insulation is a must if you're electric, makes everything quicker and uses much less energy.

 

[iralosavic]

I run a 2400w element in my 36 litre kettle and it will boil the wort hard enough to have it jumping out of the pot at any volume over about 28 litres. It's pretty heavily insulated though.

I lived in a house a couple of years back where the fridge would struggle to hold 4 degrees, the stove never worked properly, and all my oil heaters would never get hot enough to heat the place in winter. My missus copped a shock one day from the tap and we called a lecco in to take a look and apparently the house was so badly wired that the outlets weren't supplying enough juice. One call to the power company got an emergency team out there to fix it up, because the lecco told them that my missus had got a shock, which made it an emergency. Apparently.

Might be worth getting a pro to check your power supply out.

Hmm you could be onto something here - I've always been suspicious that this place has something dodgey going on with the electrical work. For example, I have a 2.1 studio monitoring speaker system that worked perfeclty right up to the day I moved in here and a week after having them plugged in all the fuses blew and no matter how many times I replace them, they all blow instantly now.

I will try the same volume boil out at my brewshed (offsite) on the 15a socket and see how it goes. If it still can't maintain a rolling boil, I'll play around with insulation and go from there. The problem with swiching to a 3000w+ element is that I would be limited to 15a outlets, which I don't have access to at home.

Aeroflex hey... where do you get it from?



Cheers

 

[QldKev]

Hmm you could be onto something here - I've always been suspicious that this place has something dodgey going on with the electrical work. For example, I have a 2.1 studio monitoring speaker system that worked perfeclty right up to the day I moved in here and a week after having them plugged in all the fuses blew and no matter how many times I replace them, they all blow instantly now.

I will try the same volume boil out at my brewshed (offsite) on the 15a socket and see how it goes. If it still can't maintain a rolling boil, I'll play around with insulation and go from there. The problem with swiching to a 3000w+ element is that I would be limited to 15a outlets, which I don't have access to at home.

Aeroflex hey... where do you get it from?



Cheers

I'm interested if you can post back how you go with the extra insulation. I'm looking at setting up a single brew system for experiments and beer that I only want a single batch off, eg Wiezen. I was thinking of using a 2200w element to run it.


QldKev

 

[matho]

what is the diameter of the opening of the keggle?

 

[iralosavic]

what is the diameter of the opening of the keggle?

I cut it to fit a 30cm lid.

 

[iralosavic]

I'm interested if you can post back how you go with the extra insulation. I'm looking at setting up a single brew system for experiments and beer that I only want a single batch off, eg Wiezen. I was thinking of using a 2200w element to run it.


QldKev

No worries, Kev. Although it may be a while before I get around to it as my wife is full term pregnant at the moment and the time off I have is not supposed to be used up in the brewery.

 

[stux]

No worries, Kev. Although it may be a while before I get around to it as my wife is full term pregnant at the moment and the time off I have is not supposed to be used up in the brewery.

I made a kegerator in mine

 

[QldKev]

I made a kegerator in mine

what; in the wife? :huh: