Using Mash Tun PID to fire HLT element when mashing

chris.beard82

Has anyone tried wiring the Mash Tun's PID to fire the HLT element when mashing? Just thinking that this might be a slightly better way of regulating the water temp in the HLT to control the mash temperature as it is taking it's reading from the Mash Tun probe. An auto tune to stop it overshooting would probably be a good idea but otherwise seems to make sense.

Has anyone done this or have any thoughts?

wscottcross · Posted: Sun Sep 04, 2016 9:02 pm Post subject:

I guess it could be possible to do, but the lag would probably result in too much hysteresis and likely overshoot. It's just as easy to set the HLT a couple degrees hotter depending on the losses in your system and let it go.

David_H · Posted: Fri Sep 09, 2016 2:01 pm Post subject:

It will work, but I think the lag time would get to be a problem. The PID will learn itself to hold the mash temperature correctly, however, I think this will be in the steady state period while Mashing. As soon as you attempt to raise the temperature of Mash Out, you leave the steady state environment and your HLT temperature will drastically overshoot the temperature in the Mash Tun. You could give it a try with just water and let us know how it works.