MyloFiore wrote:I would think that placing the thermowell at the output of the coil wouldn't be the best solution either for a HERMS setup. It's going to shut off the recirc as soon as the first bit of wort passes through it. Most, if not all of your mash will be at a lower temp.
Mylo
If the flow rate is very slow, the heating element does cycle on and off but with the temp probe at the output of the heat exchanger you are able to control the temp of the wort landing on top of your mash. In practice my flow rate is high enough that the element will stay on for quite a while as it heats the mash. In previous versions of my electric system when I was measuring at the output of the mash and before the heating element, I would overshoot my set temp by 10 degrees, moving the probe to the middle of the mash would cause a less severe overshoot but I still predict an overshoot on an system using an external heat exchanger.
Whatever you choose, just stick with for a few brew sessions so you can determine if you can control the system well enough to maintain the temp you want.
My system now is a cooler with PVC manifold, this drains into a T with a digital temp probe, then the wort goes to my electric heat exchanger, after passing by the element, it passes by the LOVE control probe on it's way to the pump which takes the wort back to the top. In practice, the love control temp and the output of the mash tun measure within 1 degree of each other for the whole 60 minute mash if it is a single temp mash. If I have to do a step mash. I can adjust the LOVE control up to 170 or so and watch for the temp at the bottom of the mash to start moving, once this happens I can adjust the LOVE control down to my desired set temp and it usually stabilizes in 10 - 15 minutes so that both thermometers match. On a 10 gallon batch I will infuse with boiling water because the 1500 watt element just takes to long.
Linc
