Heating buttons (1900w vs 500w)?

#1

I’m using robobrew gen3.0.
Few months ago I dropped robo and it was dented. So there is a gap between body and false bottom.
I usually do mashing as below using 1900W
S1 : 122F , 15min
S2 : 150F , 75min (including temp increasing time)
S3 : 172F , 15min (including ramp increasing time)

After finishing boiling I found bottom got scorched and stick with dreg of grain. During boiling I turned on both heating switches(1900w and 500w).

Is the reason of scorching gap? or Should I use 500w(only) during mashing and 1900w(only) during boiling?

#2

You’ve pretty much come to the same conclusion I did. I think I read in the manual that the 500w element should be the only one in use during the mash because the 1900w one could damage the malt pipe or something.

During the boil, I found that the 500w one was not enough to sustain the boil but the 1900w one was - and I also experienced the slight burning on the bottom so I leave the 500w one off during the boil to try and minimise this

#3

I’ll try to use only 500w for mashing next time. But it will take so long to ramp temp up.
And should use 1900w only for boiling.

#4

Oh for the mash use both to get the water up to temperature, and then turn off the 1900w before inserting the malt pipe and tipping in the malt (at least that’s what I do anyway)

#5

“Few months ago I dropped robo and it was dented.”

If there’s a gap in the bottom of the malt pipe and mesh screens, that’s not good. If grain is getting through, it may be the cause of the scorching. Have you done many brews in the robo? Was this one any different - e.g. more grain than usual ? Did you get any overflow down the centre pipe? - Could you get a piece of silicone tubing and split it length ways to fill the gap?

I’m guessing you’re in the US so 110VAC? My results may be different as we’re on 240VAC.

I mostly set my mash in temp at 78C with both elements on and wait for it to come up to temp. By the time I’ve finished dough in, I’ll set it back to 68C (I find the indicated temp is about 2 deg C higher than measured with a thermometer). I’ll still leave both elements on during the re-circulation - I run that generally for an hour, maybe 90 minutes … The thermostat will keep the temperature pretty close to what I want.

For the boil, I set the robo temp at 105C, both elements on and let it go nuts for an hour (lid off). I may get a little staining on the base where the elements are but that wipes off pretty easily at cleanup…

Apologies for talking Celsius … but you get my drift.

[Edit] forgot to say my RB is a 35L / 5 gal …

Hope this helps.

Q