One thing I thought of and this is probably a ridiculously stupid question but with the element concealed, how are you supposed to clean it?
The only parts that need cleaning are those inside the vessel. The plate at the bottom seems to develop a vague film of cooked on protein in the central raised zone under the hop filter. This is probably where the actual element is and probably runs a bit hotter. This just wipes off with one of those green, slightly abrasive kitchen scrubs - I mean those yellow rectangles of sponge with a green scrubbing side. It really just needs sponging off. The boiler cleans up really well. Obviously, you can wipe the outside too. If you have bought a nice shiny object, it's nice to keep it that way. :)
I mash mine in the following way:
- Bring 12 or 15 litres to 75c (CHECK with THERMOMETER)
- Dough in grains and stir to ensure good mixing
- Check temperature IMMEDIATELY and adjust with cold if needed to hit desired mash temperature. If it comes out too hot you don't want it there for long or you may destroy the amylase enzymes - especially beta-amylase which is damaged at over 70C.
I had to cool mine a bit by adding perhaps a couple of pints of cool water to get it to 65C. It had arrived at 69C before I added the cold water. I had a grain bill of about 3.2KG. Obviously the amount of grain affects the drop in temp from strike temperature to mash temperature. More grain than my example would need more water for mashing. I think the typical amount is 2.5 - 3l per kilo of grain.
During the mash the temperature stayed quite stable for most of the hour, dropping from about 65C at the start to about 63C by the end. A larger mash volume would hold its temperature better. The insulation works quite well.
If you were going to use the thermostat for maintaining the mash temperature, I suspect that the overshoot of the thermostat might make it tricky to rely on that to maintain it exactly. Also, if you do BIAB like I am doing just now, you might burn the bag if the element came on. I just didn't need to use it, relying on the insulation and it worked.
After the mash and draining my bag, I dumped the bag in a large bowl, and emptied the first runnings into my 12l stock pot. I then put about 15 litres of cold water into the boiler for a dunk sparge and took it up to 80C. Then I added back the grain bag and steeped it for about 15 minutes, drained the bag again, squeezed it into the bowl and added back the resulting liquid from the bowl.
I then put the heater on again to raise temperature for the boil and emptied my first run off wort back to the boiler from the stockpot and adjusted the water level in the boiler by adding more cold water to take the boil volume up to about 23 litres - maybe a half inch below the full mark.
Even at this level, slightly short of 25 litres, there are some points in the boil where you may get a rise of foam that could boil over. I felt more comfortable keeping it slightly less than full and topping up with a litre or two of boiling kitchen kettle water as needed as the liquor boiled down.