In an effort to brew outside of my kitchen but not actually outside, I am considering a miniature recirculating kettle/mash tun system with an element in the kettle.
I have read extensively about the benefits of PID control for these setups, especially when considering that with the large amounts of water used for 5-10 gallon batches the PID offers superior control with no overshoots.
Considering that my batch sizes range from 1-1.5 gallons, and that the total thermal mass in my brew sessions (< 2 gallons between the kettle and mash tun) is fairly small, will the STC-1000 work as a controller for this setup? Can I expect fairly accurate temps or should I just pony up and plan for a PID?
While the stc-1000 would work, I would go with the PID. It is smarter than the stc-1000. Also the stc-1000 is only capable of 10A max, if that matters.
The amperage isn’t really a concern. You could always remove the internal relay and feed an SSR from the STC-1000. My real concern would be degree of accuracy, which would definitely be lower than the PID, and if I can live with that.
Not that there is anything wrong with what i’m doing now. My single kettle and mini mash tun works great on the kitchen stove.
If you are going to use an ssr, spend the extra $20-30 on a pid.
If you are continuously recirculating, the accuracy of an stc-1000 might be fine. I use one for my ferm freezer and it would overshoot by a couple of degrees since I am using a thermowell. It got much better when I put a couple of fans in the freezer, but a PID would eliminate the overshoot even further.
One other thing is the stc-1000 doesn’t have a manual mode, so you might need to account for that somehow.
I’ll plead ignorance here: Since I have never owned a PID controller, I am just going off of generally accepted opinion that PIDs are more accurate and limit overshoot.
With the small thermal mass i’ll have, and the absence of an HLT to add to that thermal mass, i’d say that it is probably just fine for my application.
In which case, wouldn’t small thermal mass (relative to the heat source) increase the likelihood of an overshoot? I don’t think it would be a practical concern though, provided you size the element properly. You can set the differential to whatever it takes, all the way down to ±0.1°C if needed.
Last spring the rims pid on my system failed a few minutes into the (60 min) mash. I quickly wired up a spare stc1000 to the rims tube and the thing seemed to do a comparable job at controlling the mash temp for the rest of the mash. I was pretty surprised. I wouldn’t try and build a 10 gallon e-rims system with the stc1000s but I bet you could do a low powered system with them.
Hope that helps
I’ve been using my “$50 Mini eHerms” Set up for the past couple of years. Works like a champ and does exactly what I need it to do. It has a bit of trouble keeping temp during the winter months but, I can’t expect much more out of a 1000w burner -
The shiny Keg is the HLT and the pot is the boil kettle. We rotate it off the burner depending on whats happening. The keggle on the lower shelf is the mash tun with a false bottom recirculated through the mini-eHerms which contains a hot plate controlled by the STC-1000 which heats the HEX pot and coil. Works great for 5 and 10 gallon batches to keep the temp regulated during the mash. We’re going to insulate the mash tun because the SS just does not hold temp well, especially during the winter months.
I have a HotRod Heat stick that i’m going to use in a bigger pot since it’s a 2000w heating element and it’ll help with temps a whole lot quicker.
You are correct, the STC-1000 will not be able to handle the wattage so I’ll be moving to a PID controller with relay to be able to handle the amps. I saw a controller on Amazon that suits my needs and will do what I want it to do with the HeatStick. I’ll probably use the STC-1000 for either my kegerator again or sous vide.
