Funny Boiler boil

[photek1000]

Used my Peco boiler for my second BIAB brew today, a couple of issues.

Had a funny on\off rolling boil in the last 20 minutes of a 90 minute boil, shown in the video, which I can't get to embed for some reason.

https://youtu.be/q9YU-aSgB5Y

Any ideas what could cause this, there is no thermostat it's a basic boiler 2.4KW element.

Apart from that a brew of two halves, hit my target gravity of 1.052 with a Hobgoblin style beer, but I'm still only hitting 55% efficiency, something to work on.

I also came in 2-3 litres under the 19 litres I was aiming for.

Either way, still a fun day brewing and hopefully tasty enough once fermented\conditioned.

 

[IainM]

That behaviour from the boiler is odd, so I can't help there. For increasing BIAB efficiency, I've found that freshly and finely crushed grain, mid-mash stirs, epic bag squeezing, and a decent mash-out temp batch sparge have worked wonders for me; my last BIAB had a mash efficiency of 80%.

 

[photek1000]

Thanks for the reply, I think the size of the grain crush is definitely a factor, the grains so far are all off the shelf pre-crushed bags for recipes and probably not that fine.

This brew day I stirred the mash twice, to get it nice and mixed in the mash, I sparge in a separate bucket at the suggested 75c temp and then top up the boiler, but I think some epic squeezing is in order next time :-)

 

[wfr42]

Do you have a false bottom - I think the geterbrewed option comes with one?

I added one (a false bottom) at christmas and have seen something similar with my two brews to date with it, I've found stirring helps a bit, but have had more spill overs than previously.

 

[hoptoit]

Looks like it's power failure to the element. Is there a loose connection in the plug top or socket it's plugged into.
I always squeeze bag after sparging, some say it gives unwanted tannins. But I've enjoyed everything I've brewed.

 

[Leon103]

Was the element clean? It looks a figerous boil and then nothing, might be why you brewed short

 

[photek1000]

I was thinking along both of those lines, it does have the false bottom from Geterbrewed, and it does look like the power cycling for what ever reason, it's in a good socket, I have the house to myself when I'm brewing so far, so apart from the radio nothing else is drawing any significant current on the downstairs ring.

So two things to try, annoyingly separate to nail the source, remove false bottom and try a different extension cord/socket.

And definitely some bag squeezing is called for.

 

[photek1000]

Was the element clean? It looks a figerous boil and then nothing, might be why you brewed short

Yes, it's only the second use and it did it also on the first use, I scrub the element after use, it's still pretty shiny.