Using mash PID to recirculate

[everty2007]

So I built a Kal clone styled system. The other day is was brewing and during my mash I had an idea. I usually have my HLT set higher then my mash temp to get mash up to temp faster and then it is ready for the next step.

So my HLT would be at 170 and my mash at 154. The way i do it now is turn the pump on and off as I achieve my mash temp.

My thought was that maybe I could put in a 3 way switch for the wort pump so that I could have off - on - and PID controlled.

Any thoughts on changing to a 3 way switch with one side controlled by the mash PID that is currently controlling nothing? Could I just run the wires from the PID to the switch or would I need something in between?

Thanks for any thoughts

Tyler

 

[jesserizzo]

This should be simple. Most PIDs have a built in relay that can switch a few amps, so you would only need to add the 3 way switch.

However, why do it this way? Why not do it the Kal way and set your HLT temp to the mash temp and recirculate the whole time?

 

[alien]

This idea has been floated a few times. It certainly can be done but there are a few question marks about the technique. It's not clear where the best place to put the probe is. And without constant recirculation, you will probably need to stir the mash to make sure the temperature evens up when the hot wort from the HEX drops back in.

 

[jeffmeh]

There should not be any doubt that exposing the wort in the HERMS coil to higher temperatures than your ideal mash temperature will yield a different result than having it go through the coil at mash temp. That does not mean that you cannot get good results, but you will be denaturing some of the enzymes when going through the coil at higher temps.