And I am not saying the downsides of repurposing the HLT are all that great, but if you have the storage space and few extra bucks, it can make your brewday a bit less chaotic, especially when going solo. Although, there are entire processes that can be eliminated to make things easier and less gear intensive with very few or no drawbacks. BIAB is one way I have been trying out, although it does increase the size of the vessel required unless you do some workarounds.I'm not trying to convince anyone that a single vessel is the best way to do things, I just don't see how adding a second vessel would be an improvement for my particular system.
I meant one more complete pot setup, along with the additional storage required being the main, if not the only, benefit of reusing the HLT instead. If power is available, a cheap 110V heater element makes for a compact HERMS pot.And one less temp controller, and one less heat source..... Either that or a more complicated process with moving pots of hot water around and/or controlling the HLT manually.
I expect that a HERMS volume 1/4 the size of the HLT is more than enough buffering/damping for even a simple controller, and as has been commented recently- true PID control is all but useless for this type of system. When I used to do HERMS (combining gear with a friend), I think I used one ~1/3 of the HLT volume, and it was more than enough, even when doing it manually without the controller. I relocated temporarily, and have been reduced to using direct fire BIAB. The BIAB part I like, the direct fire mashing is a pain, at least without acquiring yet more large gear- like a basket.It does make ramping temps much slower, but the larger thermal mass makes it easier to hold a steady temp, especially when using a simple on/off controller rather than a PID.
Every extra step adds one more ball in the air. Some juggle better than others. Having a separate pot makes things simpler that way, and reduces the urgency of some tasks, at least for me.Like I said, it depends on your process. I don't do much juggling at all. To switch from dough-in to HERMS I simply add cold water.
I with you on the batch sparging. Fly sparging is only good for style points and $1 worth of grain. IMO there is also no reason to worry about sparge water temp, except for it being too hot. Someone reputable did a thorough test that debunked the benefit of heated sparge water for anything except reducing subsequent time to reach boil. I still like a mash-out though, but have little rationale as to why when batch sparging or BIAB, since it can be done just as effectively in the kettle. Maybe a bit more starch is cooked out of the grain, but I am grasping.I batch sparge, and IMO there's no reason to mash out when batch sparging, so no temp juggling there. I fire the HLT burner up as soon as the MLT starts draining, and by the time the first runnings are transferred, the water is up to sparge temp. It's a very simple, fast, and easy process
I also dough in with mash temp strike water (+2F maybe), and ramp back up to mash temps. Probably unnecessary, and a lot of extra stirring, but that will hopefully be minimized with the mash coil. Again no real ground to stand on, other than maybe treating the proteins a little more gently.
If you don't have any issues with batch sparging, BIAB is a small leap and will get you down to at most 2 if you still want HERMS. You can even add a dunk sparge in a spare bucket to get very close to or even match batch sparge efficiency. If not, its nothing $2 worth of grain won't remedy. The HERMS pot can be sized to fit inside the BK for storage. For anything larger than 10 gal batches, I am finding that a basket is a necessity.I'd actually like to make some changes that allow me to reduce my rig from a 3 vessel to a 2 vessel. I may be moving out of state soon, in which case I'd likely sell my current set-up and build a single vessel system.
The stir motor is key, along with insulation, and a very thin, or even better a full volume, mash. A little localized temp variance is probably a good thing, as long as the upper limit is controlled like with HERMS, and the mash is manually stirred a few times during the mash.My HEX coil is mounted to the underside of a lid that fits all of my kettles, allowing me to use it in many different configurations. I tried the method you're describing, but found there was too much temp variance between the areas close to the coil and further away. I think it would have worked better with a stir motor, or if my MLT were better insulated so that the HEX was only providing minimal amounts of heat. I've added a lot of insulation to my MLT since then, and might try it again.
Your setup is very close if not exactly what I am building. I will also use the stir motor when chilling and to get the whirlpool going. Although, I haven't had much luck with the whirlpool cone lately with the quantity of flame-out hops I have been using. I have a plan to reuse a soon to be acquired mash basket (needed for 50lb ~25 gal BIAB) as a hop spider/strainer to get rid of most of the hops after chilling, then replace the stirrer lid for whirlpooling. I will also be squeezing the nectar back out of those thieving bastards. I don't mind a losing a couple of bucks in grain to efficiency, but those hops are sponging up a lot of what is close to final product. Maybe less big flameout adds and increased dry hopping is a better solution.
I will not be pumping any product with my revised BIAB setup, but it does require elevating the kettle to fermenter height. The mash coil pump can serve dual duty as a ice bath pump for the chiller in the summer.I also like to reduce the time the wort spends being pumped. Since adding the insulation I've started leaving the pump off for the first ~30min of the mash. I'm familiar enough with my system that I can hit my temps without the aid of the HERMS, and I don't notice any difference in wort clarity between an hour of re-circulation and 15 min of re-circulation.
I am always jacking with things too much to get really dialed in, but even if I did, I like having the ability to recover gracefully when the SHTF- something systems with no mash heat infusion, like coolers, don't allow.