Did my next brew last night. Made a nice Pale Ale/Session IPA, depending on how you look at it. Of course, each time I brew, I learn new items/issues with my system. Here are the problems/issues that popped up that I need to address:
1. My efficiency has not been stellar, so I decided to tighten up the gap on my mill a scosche... Well, that resulted in much better efficiency but it also resulted in a stuck-ish mash. I needed to stir it in the beginning to keep it going. After that it was ok. I have a NorCal false bottom, so not sure what the deal is. My recirc rate may have been a little high, but not out of line IMO. I had a stuck mash on my pumpkin beer, but was never expecting one here with just malt. I am going to leave it and make sure I do a very good grain condition before crushing next time. I was in a hurry and did it kinda half-assed because I didn't rest the grain after conditioning it.
2. During sparge, on occasion the flowmeter/Arduino said the flow was zero. That caused the Arduino to temporarily open the proportional valve, which solved the problem, but not sure what the deal is. I suspect either noise or just a cheap-ass flowmeter=cheap-ass results. Later on, the Arduino locked up, but only during the AutoClean cycles. I think this is due to EMF/voltage spikes from the inlet water valve solenoid. I will add a suppressor/flyback diode to remedy this. Also I got my eye on a non-contact magnetic/inductive flowmeter on eBay...
3. During the sparge, the RIMs tube water temp was all over the place. This has often been an issue with such a quick responding loop that occurs from direct sparge water heating. It has proven difficult to tune. I am also convinced the BCS PID has errors in it and cannot correctly time fast output cycles. I changed it to duty mode at 65% and it held like a champ. Going forward I will just use this mode. With consistent water temp and tightly controlled flow rate through it, there is no reason not to. The good thing is this will free up a BCS output (was using two to take advantage of different PID parameters) because I have no more outputs left! Thinking a valve to control the oxygenator or an automatic hop/adjunct adder. Any votes?
4. During whirlpool, my Chugger decoupled again. I learned that without any restriction (head pressure) and near boiling fluid, this is causing it. Not exactly sure why. I didn't see bubbles so I don't think it was cavitation from the pressure change. When I added a small restriction by placing a clamp on the hose leading to the whirlpool arm, it resolved. I need to add a nozzle to the whirlpool arm for more velocity anyway, so this should take care of that.
5. The AutoClean rinse process worked but didn't exactly clean out the debris. The reason is the junk drawn through the bottom drain recirculated right back into the kettles because it is a closed system. I have two filters on hand but did not have the fittings yet, so I could not install them. I am going to try them, and if they do not work, I will come up with a drain/feed bucket system to strain out debris using a bucket of water and a whirlpool effect. Also, the sprinkler heads worked but they aren't "violent" enough. I need something rotating that directs more water in one place. I would like to make a rotating T-bar with a nozzle on one or both ends to make it spin, but a quick search revealed not much in the way of cheap rotating fittings. Any feedback is appreciated.
6. The real shocker of the night was when I went to run the AutoClean process. I use the MLT sight glass sensor to measure the fill height of the kettles. Since the MLT and the BK are connected during the fill, they automatically level. Once the sensor indicates there is enough water (to cover the BK element), it switches the valves separating the two and begins heating both 5500W elements to draw the full 50A. While it was filling, I started to smell something... I went over to take a look thinking it was something in the control box as I haven't pulled 50A since my initial tests following the build. Well, it was the BK element which was not under water. It was dry-firing and had a nice, bright, cherry glow to it! Slammed the E-stop and let it cool down. Smelled like crap but it sure took care of the gunk that was on it following the boil! As it turned out, the MLT sensor tripped on a water droplet or two that was running down the inside of the sight glass! This was enough to tell the BCS to go to the next state, which was the heating state. Fine tuning it's sensitivity, and adding one (was already on order from eBay) to the BK sight glass as a safety will prevent that from happening again. The element worked fine after that but I will probably order a replacement just in case.
Of course in the end, I made wort! It was bubbling hard 12 hours later, so I will have beer. The sample was delish and I hit the numbers dead-on. I am happy to be making progress, have the big stuff out of the way, and only have some final-ish programming and minor updates. My system is almost as I originally visioned it. I don't really know what left I have to add or upgrade. So what am I going to do now?!? Building is 90% of the fun!
