DSPR320 questions

[DonT]

I'm doing my first water only run-through of my 3V HERMS with a Brew Buddy II. I had set the boil control at 212* for 1 hour. I hit the RUN button, covered the kettle and went back inside because it's 100* in the garage. Came back out 20 min. later to check on it and it was already boiling vigorously. Temp readout was only 207*. Stuck my Thermapen in there and it's at 209.3. Of course the timer had not started yet because the temp never reached 212*
What is happening here? What am I missing?
EDIT
Ok, I've calmed down a bit. Boiling point in my area is 210.95* so that makes it an almost two degree difference from what I measured. I'll need to adjust the offset to match. I guess I'll use 209* as the start point.

 

[doug293cz]

I'm doing my first water only run-through of my 3V HERMS with a Brew Buddy II. I had set the boil control at 212* for 1 hour. I hit the RUN button, covered the kettle and went back inside because it's 100* in the garage. Came back out 20 min. later to check on it and it was already boiling vigorously. Temp readout was only 207*. Stuck my Thermapen in there and it's at 209.3. Of course the timer had not started yet because the temp never reached 212*
What is happening here? What am I missing?
EDIT
Ok, I've calmed down a bit. Boiling point in my area is 210.95* so that makes it an almost two degree difference from what I measured. I'll need to adjust the offset to match. I guess I'll use 209* as the start point.

You should probably use ~205°F as the "Start Boil Timer Trigger." This will drop your power just before you get to the boil and reduce the chance of a boil over. Default is 200°F for the reduce from accelerated heating trigger, and 208°F for the start of boil timer trigger. Maybe just stick with those until you have a good reason for changing them.

Brew on

 

[DonT]

That sounds good. Thanks for your help!

 

[doug293cz]

To fill in the background of what's going on:

You don't ever set the boiling temperature. The nature of the liquid and local atmospheric pressure determine the boiling temp, and there is nothing you can do to change that. All changing the power will do is vary the boil vigor, as long as you have enough power to reach whatever the boiling temperature is.

The EZBoils have a feature that applies full power (or another % power that you specify with "bout" (boiling acceleration output power) up to a temperature that you specify with "bASt" (boiling acceleration set temperature.) This allows you to heat up rapidly, but then automatically reduce the power before you reach boil in order to avoid a boil over. There is another temp set point: "btSP" (boil timer start temp) that determines the temperature at which the boil timer starts. You must set btSP lower than your local boiling temperature, or the timer will never start.

Brew on

 

[Bobby_M]

I'm just filling in something I didn't see mentioned yet. Make sure your boil control DSPR is actually in "BOIL" mode. Short press of the knob, rotate to boil, click. The boil mode's input is power selection only as noted by the "P" and then the number. The only time you'd ever have this dedicated DSPR set to mash mode is if you were doing a kettle sour and needed to hold the wort at 90F overnight.

As Doug mentioned... you set the boil parameters deeper in the menu. Long press... go to boil.... I use bASt and btSP of 208F since we boil at 212 here.

 

[DonT]

I'm just filling in something I didn't see mentioned yet. Make sure your boil control DSPR is actually in "BOIL" mode. Short press of the knob, rotate to boil, click. The boil mode's input is power selection only as noted by the "P" and then the number. The only time you'd ever have this dedicated DSPR set to mash mode is if you were doing a kettle sour and needed to hold the wort at 90F overnight.

As Doug mentioned... you set the boil parameters deeper in the menu. Long press... go to boil.... I use bASt and btSP of 208F since we boil at 212 here.

If you don't mind me asking, what are your mSET settings?
I did a couple of brews and had all kinds of issues with temperature stability. Afterwards, I realized I hadn't set up everything completely/correctly. And after reading and re-reading the manual I'm still not 100% about what I should setting everything at. The overshoot (oscr) and the ATTE confuse me.

Thanks for any help you can give me. I'd like to get things set up or at least understand enough about whats happening to make adjustments on the fly.

Cheers!

 

[doug293cz]

If you don't mind me asking, what are your mSET settings?
I did a couple of brews and had all kinds of issues with temperature stability. Afterwards, I realized I hadn't set up everything completely/correctly. And after reading and re-reading the manual I'm still not 100% about what I should setting everything at. The overshoot (oscr) and the ATTE confuse me.

Thanks for any help you can give me. I'd like to get things set up or at least understand enough about whats happening to make adjustments on the fly.

Cheers!

Can you describe the characteristics of the temperature instability? Also, what vessel is the heating element you are controlling in, and where is the temp probe located? What is your rated element power, and approximate volume volume of liquid in the vessel being heated?

Brew on

 

[DonT]

I was having issues with keeping the temp in the mash where I wanted it. There is a delta between the HLT and the mash that i haven't figured out yet. I'm still getting to know the idiosyncrasies of the system. For instance, I discovered during my first brew that I needed more water in the HLT during recirc because it wasn't covering the coil enough. That helped...

As you can see, I have one probe in the outlet for the HLT, which goes to the HLT controller. One in the outlet for the coil and one in the outlet for the MLT.
This is the element I'm using and I had started with 12g in the HLT and had transfered ~4.5g for strike water.

 

[Deadalus]

I was having issues with keeping the temp in the mash where I wanted it. There is a delta between the HLT and the mash that i haven't figured out yet. I'm still getting to know the idiosyncrasies of the system. For instance, I discovered during my first brew that I needed more water in the HLT during recirc because it wasn't covering the coil enough. That helped...
View attachment 746556

As you can see, I have one probe in the outlet for the HLT, which goes to the HLT controller. One in the outlet for the coil and one in the outlet for the MLT.
This is the element I'm using and I had started with 12g in the HLT and had transfered ~4.5g for strike water.

It helps to recirculate the water in the HLT, particularly as there is no flow near your temperature probe. It's way off on mine if I start heating the HLT and don't do it. Sometimes I forget to do it and go mill my grain, then stand around an extra few minutes wondering why my water isn't heating up quickly only to find out I'm blowing past the strike temp. Never a good start to the brew session when I do that.

 

[Deadalus]

I like to keep the coil just covered. The strike water temp will be above mash temps so leaving a little room allows you to add water to drop the HLT temp down closer to the mash.

I've got to get a pair of those green gloves. They would come in handy for fiddling with the MT screen and pickup.

 

[doug293cz]

As @Deadalus said, you should recirc the water in your HLT.

With a HERMS system it is typical to have a few degrees offset between the HLT and MLT temps (MLT will be lower.) To get stability, you really need to determine what the offset is for your system, and then add that offset to the set temperature for your HLT to maintain the desired mash temp. The offset will likely depend on your mash volume, so if you do different sized batches, or widely differing grain bill sizes, you will need to characterize how that affects the HLT - MLT offset.

Don't try to control the temp using the MLT temp probe. The time delay for the mash temp responding to changes in the HLT temp will likely cause the system to oscillate.

Brew on

 

[DonT]

I have been recirculating HLT during warm up and mash to keep the temps stable. I think I have the control probe in the HLT but I may have mixed them up and that may explain my troubles.
@doug293cz , you talk about offset. Are you referring to the probe offset to adjust for an inaccuracies? Or is there another setting? What about the overshoot correction? I'm not sure how to handle that or the ATTe (attenuation?) settings....

 

[doug293cz]

I have been recirculating HLT during warm up and mash to keep the temps stable. I think I have the control probe in the HLT but I may have mixed them up and that may explain my troubles.
@doug293cz , you talk about offset. Are you referring to the probe offset to adjust for an inaccuracies? Or is there another setting? What about the overshoot correction? I'm not sure how to handle that or the ATTe (attenuation?) settings....

Due to the very nature of HERMS systems, they have a temperature offset between the HLT temp and the mash temp. Thermodynamics requires this, unless you have 0 temp loss in the plumbing between the HERMS coil and the MLT. The offset parameter in the EZBoil (Pb) is for correcting temperature probe errors, not the inherent HERMS offset. If you used the Pb parameter to compensate for the HERMS offset, then your strike water would overheat every time. So, you have to manually do a correction for strike water temp or mash temp, and using Pb to eliminate the HLT/MLT temp offset may require you to adjust the parameter when your mash volume changes.

Don't worry about the ATTe parameter (leave it at default) unless your system temps oscillate even after you compensate for the inherent HLT/MLT offset. Increasing the ATTe value if you can't get rid of the oscillation by using the recommendations already given will reduce the oscillations, but will also slow the system down when making temperature changes.

Brew on

 

[Bobby_M]

Bad temp oscillation is usually due to putting the HLT's temp probe in the mash wort plumbing loop or in the mash tun itself.