struggling to get a hearty rolling boil going

[Paul Dolan]

Hi There, I am quite new to here and very new to brewing, in fact I have not yet completed my build. it is actually built now and I am testing it with just a water run through and hit a snag or two!
I have a Boilermaker G2 for my kettle, it's 115 litre version and I have a 3kw ULWD element in it. Although I am planning on only doing small batches (poss 25 litre boil volumes) to start with, so that is the volume of water I am testing with, and it just won't get rolling, like I see brew day videos showing. am I just underpowered for the size of the pot, it's almost like the pot itself is acting like a heatsink. I have read that the surface area of the pot being quite large in comparison to the volume I am boiling will not help either.
The other thing is getting rid of the steam, I installed an extractor fan close to the kettle and it seems totally ineffective?
Any help would be really appreciated, Thanks, Paul.

 

[kelper]

Can you make an insulating jacket and a lid?

 

[britton]

3kw heater should easily boil 25L, are you sure it's 3kw?

 

[Paul Dolan]

Can you make an insulating jacket and a lid?

The boilermaker has a lid but from my reading I am understanding that you shouldn’t boil with the lid on anyway is that not correct? I have tried with the lid covering more than half of the opening and it made no difference, it does start to bubble around the element but not a proper rolling boil. I have also tried a basic jacket which also has little effect.

 

[Paul Dolan]

3kw heater should easily boil 25L, are you sure it's 3kw?

I bought it from angel home brew it’s a 3kw lwd ripple kit they have. I was wondering if it was to do with the fact that it is such a big pot with only a small volume being boiled.

 

[simon12]

Sorry I can't really help except something is definitely wrong. The large vessel could soak up the heat for a while and the excess surface area of both the vessel and the liquid will disperse it more but 3 Kw in 25l is so much. ie my 30l plasic kettle with a 2.4Kw element has a boil far to vigorous and a 200l kettle I used to have could maintain a rolling boil (when full) with 1 x 3Kw element but took ages to get there even with 2.

 

[Paul Dolan]

Thanks Simon, appreciate your input.

 

[simon12]

I forgot to mention the 200l boiler was seriously well insulated and had just a small chimney in the lid to allow the steam out.

 

[Cwrw666]

You could of course just have a faulty element?

 

[kelper]

You could of course just have a faulty element?

Yes! is there any way you can measure the current draw? Do you have an energy monitor? It could have a short circuit bypassing some of the element. A Kill-a-watt or similar would tell you how many watts it's actually using.
I use a smart plug, which allows remote monitoring

 

[An Ankoù]

The boilermaker has a lid but from my reading I am understanding that you shouldn’t boil with the lid on anyway is that not correct? I have tried with the lid covering more than half of the opening and it made no difference, it does start to bubble around the element but not a proper rolling boil. I have also tried a basic jacket which also has little effect.

It will come to the boil much quicker with the lid on, but will then immediately boil over. If you stick a probe thermometer over the lip of the kettle, that'll allow you to keep an eye on the temperature and provide enough of a gap for the steam to escape. This is the sort of thing with a scale from 0-250 F, not the scale shown below.

 

[foxbat]

You don't need it to be jumping out of the pot. Some of those videos on youtube are ridiculously over powered and achieve nothing except blowing off steam into the atmosphere. In fact the LODO brewers who are obsessive to the n-th degree about wort quality strongly advocate little more than a simmer. A gentle 'eruption' above the element that causes all of the boiling wort to circulate is fine and achieves the three aims of the boil which are (1) wort sterilisation, (2) DMS evaporation and (3) hop alpha acid isomerisation. Measure your boil-off and refactor that back into your recipe builder so that your post-boil gravity predictions come out right.

 

[AdeDunn]

I am going to agree with the other chaps here. You either a) have a faulty element, or b) you've misunderstood what a rolling boil is. I have a 33 litre stainless steel pot, and my 2.5kw element (10amp) can manage a rolling boil with about 26 litres. Your 3Kw element should be able to do it with ease. In fact, I switched to doing smaller batches, where I am boiling about 19 litres now, and find myself running my element at about 71% power so that it's a rolling boil and not a volcanic one.

 

[bobukbrewer]

it is not controlled by a simmerstat or similar, is it ?

 

[Wobbly74]

If you have a cheap multimeter you can test the resistance across the positive and negative poles on the element (or worst case the unplugged plug) which you can work out the actual wattage draw assuming you're getting near your nominal voltage to your power point. For 240v you should be in the 19 ohm range.

 

[kelper]

The element's resistance will change as it gets hot. I measured mine cold and it was 28 Ohms for a 240V 3kW kettle. Is it definitely a 220/240V element?

 

[Wobbly74]

Resistance does increase, but not by a huge margin with ulwd elements. At least from what I can tell looking at the ammeter on my brew controller (though to be fair I haven't measured the actual resistance directly once it's hot, but my voltage remained fairly consistent under load, about 235v). 28 ohms equates to about 2kw @ 240v though?

 

[kelper]

Resistance does increase, but not by a huge margin with ulwd elements. At least from what I can tell looking at the ammeter on my brew controller (though to be fair I haven't measured the actual resistance directly once it's hot, but my voltage remained fairly consistent under load, about 235v). 28 ohms equates to about 2kw @ 240v though?

It would be helpful to OP if you were to measure the resistance of one of your elements ;-)

There is a handy calculator here that shows your element should raise 10 litres by 20C in under 5 minutes. http://processheatingservices.com/water-heating-time-calculator/

This will check if it's 3kW or less. I know some heat will be lost but this won't be large at lower temps than boiling.

 

[Wobbly74]

It would be helpful to OP if you were to measure the resistance of one of your elements ;-)

My element measured 19.2 ohms cold. So if you're in the 19 ohm range you'll be close to 3kw. Personally I wouldn't worry about resistance increase at temperature given the limited temps these run at, though you will drop a few %. Even if you measure at the plug it should give you a ball park estimate close enough for the sort of scale of difference we're talking about.

 

[Paul Dolan]

My element measured 19.2 ohms cold. So if you're in the 19 ohm range you'll be close to 3kw. Personally I wouldn't worry about resistance increase at temperature given the limited temps these run at, though you will drop a few %. Even if you measure at the plug it should give you a ball park estimate close enough for the sort of scale of difference we're talking about.

Hi Wobbly, thanks for pitching in!!
I have not had chance to measure the resistance yet but as soon as I do I will feed back. the element is running through an Inkbird pid with SSR, I am assuming that just offers a few more potential points of failure? does this alter the measurement criteria at all?
Cheers
Paul.