What Duty Cycle % for Boil Element

[BrewKaiser]

Curious what others are using for a duty cycle percentage for their element during the boil.

I have a 5500 ULWD element in a keggle. Hoping to lean on other's experiences in preparation of my first brew day on a new rig.

 

[jekeane]

I am at 100% till boil then 65% for the boil. I boil off just about 1.5g in my 10g blichmann. I would try lower but my pre boil volumes are nice round numbers as is.

 

[BrewKaiser]

I am at 100% till boil then 65% for the boil. I boil off just about 1.5g in my 10g blichmann. I would try lower but my pre boil volumes are nice round numbers as is.

Thanks for the quick reply. What is the wattage of your element? LWD or ULWD?

 

[02RedWS6TA]

Same rated element, my boil off is at 75% but the last one I did at 65% and the boil was plenty vigorous. Need to recalculate my boil off now.

 

[andrewmaixner]

Note also that the "Straight" 5500W ULWD has twice the heat/energy density (watts per square inch of surface area) as the "ripple" element, so that could affect how much energy you can run through it before risking a scorch (I personally think that matters moreso on on very high-gravity worts than on normal stuff, due to personal experience). I stick

See chart at bottom of this page: http://www.brewhardware.com/category_s/1902.htm

 

[augiedoggy]

I set my pid to go to 207 degrees then stop so it doesnt boil over unattended... thenI set it to about 75% for boiling 12.5 gallons or so or higher depending on how much boiloff I want to lose in the hour... 60% will give you a boil in most cases and 80% gives a strong rolling boil. Your kettle dimensions also have some impact on how vigorously it will boil and how efficiently the element will do it.

as mentioned above an ULWD 5500w ripple is not really the same as the straight ones.

 

[augiedoggy]

Note also that the "Straight" 5500W ULWD has twice the heat/energy density (watts per square inch of surface area) as the "ripple" element, so that could affect how much energy you can run through it before risking a scorch (I personally think that matters moreso on on very high-gravity worts than on normal stuff, due to personal experience). I stick

See chart at bottom of this page: http://www.brewhardware.com/category_s/1902.htm

also when using the straight one you want to stir the wort up well before turning the element back on if its been off for more than a few seconds so the proteins dont settle on it and scorch.

 

[andrewmaixner]

also when using the straight one you want to stir the wort up well before turning the element back on if its been off for more than a few seconds so the proteins dont settle on it and scorch.

Interesting point. I've noticed in the COBrewingSystems thread, that their system now recirculates both through the grain basket, and under the basket near the element -- perhaps for this reason as well as preventing grain overspill/overflow.

 

[augiedoggy]

Interesting point. I've noticed in the COBrewingSystems thread, that their system now recirculates both through the grain basket, and under the basket near the element -- perhaps for this reason as well as preventing grain overspill/overflow.

very likely.

 

[sensortech]

I just wired up some push buttons below my kettle to my BCS discrete inputs. I programmed in different Duty cycles for each button push. 100%, 65%, 70%, and 75%. I like to be able to speed it up or slow it down on the fly.

 

[itsnotrequired]

^damn, that's cool.

i usually set mine around 85%, i like a vigorous boil. plus i do 10 gallon batches so i'm boiling 12-14 gallons of liquid.

 

[BrewKaiser]

Appreciate all the feedback. Mine is a ripple element and reading through the posts here I plan to pre-heat in direct mode to 206 -> PID to 210 -> Duty at 70% for boil.

I'll see how that goes and will adjust accordingly. I assume I can programmatically adjust up/down on the fly mid process if needed.

First batch will be a split batch. Will start out as 13.5 Gal. After 30 min boil, I plan to collect 4 gal to be used as yeast starter. At this point I'll likely have to reduce Duty % down to 60%. The remaining wort will get hops and become a Pale Ale.

 

[Wizard_of_Frobozz]

I have a 5500w straight element and a 14 gallon kettle.

Like a lot of others, I run 100% up to boiling, 65% for the main part of the boil, then 100% after I put the immersion chiller in (temp drops a bit when I do that) and start kettle recirc. Back down to 65% once temp gets back up to 210F.

 

[BrunDog]

For those with automation, like the BCS, I recommend you do not use PID for your ramp. Use 100% Duty Cycle, then when a threshold temperature is achieved, switch to a boil duty cycle % (55-80% for 5500W and 7.5 - 14 gallons respectively) and start your boil timer. I say this because it's faster and if you FWH, isomerization is happening during the slower ramp.

Edit: whoops... basically Wizard's reco.

 

[augiedoggy]

Appreciate all the feedback. Mine is a ripple element and reading through the posts here I plan to pre-heat in direct mode to 206 -> PID to 210 -> Duty at 70% for boil.

I'll see how that goes and will adjust accordingly. I assume I can programmatically adjust up/down on the fly mid process if needed.

First batch will be a split batch. Will start out as 13.5 Gal. After 30 min boil, I plan to collect 4 gal to be used as yeast starter. At this point I'll likely have to reduce Duty % down to 60%. The remaining wort will get hops and become a Pale Ale.

What do you mean heat in direct mode to 206? are you using gas?

otherwise pid mode is what you would use all the way to 206-207 the element would be on 100% till the last couple degrees.

 

[augiedoggy]

For those with automation, like the BCS, I recommend you do not use PID for your ramp. Use 100% Duty Cycle, then when a threshold temperature is achieved, switch to a boil duty cycle % (55-80% for 5500W and 7.5 - 14 gallons respectively) and start your boil timer. I say this because it's faster and if you FWH, isomerization is happening during the slower ramp.

Edit: whoops... basically Wizard's reco.

I think this must depend on your pid calibration settings... I understand why in an automated setup that would work well since you have no fear of boilovers by using a very oversized kettle I assume but my pids always stayed on at 100% till it crept to the last couple degrees before setpoint so it didnt overshoot and Then I would take over in manual DC mode... If I left it at 100% for the climb to 207 I would have to babysit to avoid boilovers unless I set my alarm to go off at like 200 and watch it from there.

 

[BrunDog]

I think this must depend on your pid calibration settings... I understand why in an automated setup that would work well since you have no fear of boilovers by using a very oversized kettle I assume but my pids always stayed on at 100% till it crept to the last couple degrees before setpoint so it didnt overshoot and Then I would take over in manual DC mode... If I left it at 100% for the climb to 207 I would have to babysit to avoid boilovers unless I set my alarm to go off at like 200 and watch it from there.

Direct Mode above is a BCS thing... it means ON or OFF, so ON is the same thing as 100% Duty.

Yes, we agree. For manual setup you should NOT use 100% duty. It will only be a matter of when, not if, you get a boilover!

 

[augiedoggy]

Understood... You learn something new every day.

 

[Wizard_of_Frobozz]

The BCS really gives you a lot of options for control - it's one of my favorite features.

I don't bother with PID control for the boil. 100% (or as Brun said "Direct Mode") with an exit condition when I reach 210F. Once that hits, it will automatically shift to 65% duty cycle and starts the boil timer. Does a great job at preventing boil overs and it brings it up to a boil fast. I even programmed it to sound my alarm buzzer to let me know it started.

 

[BrewKaiser]

What do you mean heat in direct mode to 206? are you using gas?

otherwise pid mode is what you would use all the way to 206-207 the element would be on 100% till the last couple degrees.

As Brundog explained, in BCS terms "direct" refers to either 100% on or off.

My plan is to pre-heat wort in the BK while sparge finishes with element set at 100% (Direct "on") to 206*, hold at 206* in PID mode until sparge has completed, then step to 210* in PID mode , and finally transition to boil with Duty at 70% (may have to adjust % as this will be my first brew on the new system). I'm hoping the PID state to 210* does not cause a boil over. I'll have to monitor this. Hopefully the temp sensor will register 210* and exit to my "boil" state at 70% duty before a boil over.

 

[Wizard_of_Frobozz]

My plan is to pre-heat wort in the BK while sparge finishes with element set at 100% (Direct "on") to 206*, hold at 206* in PID mode until sparge has completed, then step to 210* in PID mode , and finally transition to boil with Duty at 70% (may have to adjust % as this will be my first brew on the new system). I'm hoping the PID state to 210* does not cause a boil over. I'll have to monitor this. Hopefully the temp sensor will register 210* and exit to my "boil" state at 70% duty before a boil over.

You probably don't need PID to for the boil kettle. That mass of liquid won't change temperature too fast; you can probably get away with a simple hysteresis control at 206-210 or so without a boil over.

One point to consider: where is your temperature probe for the boil kettle? If it's in the kettle, you won't see a very fast system response unless you are stirring the kettle as you approach boiling.

I put mine in my kettle recirc piping, so that means I have to recirc as I come up to boil in order to shift from direct (100%) to 65% duty cycle. Not a huge deal, because I am piped up that way anyway and I can just set the wort pump to be on for that process state. It works well - no boil overs at all since I started doing that.

 

[augiedoggy]

As Brundog explained, in BCS terms "direct" refers to either 100% on or off.

My plan is to pre-heat wort in the BK while sparge finishes with element set at 100% (Direct "on") to 206*, hold at 206* in PID mode until sparge has completed, then step to 210* in PID mode , and finally transition to boil with Duty at 70% (may have to adjust % as this will be my first brew on the new system). I'm hoping the PID state to 210* does not cause a boil over. I'll have to monitor this. Hopefully the temp sensor will register 210* and exit to my "boil" state at 70% duty before a boil over.

your altitude has a lot to do with what temp your boiling at... here in Buffalo NY my wort is at a rolling boil before it hits 211...

 

[BrewKaiser]

One point to consider: where is your temperature probe for the boil kettle? If it's in the kettle, you won't see a very fast system response unless you are stirring the kettle as you approach boiling.

It's at the same height as my element at about 30*. During the pre-heat and hold states the wort will be circulating as it will enter through the tangential whirlpool port from sparging. During "bring to boil" state I'll have to stir as you suggest. I'm of the foam skimming type (more so out of boredom and anal German sentiments than for any real reason) so I can gently stir while coming to boil.

Good point, though.

 

[BrewKaiser]

your altitude has a lot to do with what temp your boiling at... here in Buffalo NY my wort is at a rolling boil before it hits 211...

Yes, understood. I'm at 250' elevation. I should be close to 211 as well for boil.

 

[augiedoggy]

It's at the same height as my element at about 30*. During the pre-heat and hold states the wort will be circulating as it will enter through the tangential whirlpool port from sparging. During "bring to boil" state I'll have to stir as you suggest. I'm of the foam skimming type (more so out of boredom and anal German sentiments than for any real reason) so I can gently stir while coming to boil.

Good point, though.

My temp probe placement is about where yours is and I find stirring or recirculating is not needed in my case as the element keeps things moving pretty good as to get close to a boil.

 

[passedpawn]

My temp probe placement is about where yours is and I find stirring or recirculating is not needed in my case as the element keeps things moving pretty good as to get close to a boil.

I get huge temperature gradients between the bottom and the top of my ekettle. In fact, with my sensor at the bottom I see very little change from ambient until the top of the kettle gets almost to boil. If I'm going for boil, no care. But I must circulate in the HLT or I get pretty crazy overshoot.

 

[augiedoggy]

I get huge temperature gradients between the bottom and the top of my ekettle. In fact, with my sensor at the bottom I see very little change from ambient until the top of the kettle gets almost to boil. If I'm going for boil, no care. But I must circulate in the HLT or I get pretty crazy overshoot.

huh.. and your is placed at the same height and distance from the base?

EDIT yeah for heating to sparge or strike temps I agree I see the same in my HLT..(thats why I question people who say recirculating the HLT water with a herms is totally not needed it didnt work at all for me until I did this) . I was referring to BK use only.

 

[BrunDog]

Hey BK... I saw that ring before, but maybe didn't make the connection... IIRC it has individual holes. If you use this in your BK, it will likely clog from pellet hops, unless you plan on using a strainer/sock/cage. I don't think you are doing that since you have a tangential input, but FYI. Didn't mean to hijack thread...

 

[BrewKaiser]

Hey BK... I saw that ring before, but maybe didn't make the connection... IIRC it has individual holes. If you use this in your BK, it will likely clog from pellet hops, unless you plan on using a strainer/sock/cage. I don't think you are doing that since you have a tangential input, but FYI. Didn't mean to hijack thread...

Hope to post positive results on Monday on my pick up ring. I think I'll be OK, but if not then some form of sock/screen will be applied. There are 70+ .250" holes on the bottom perimeter. My "sanitize coil" state starts with 7 min left in the boil. The boil action should still be moving the hop debris around when this starts. Once the whirlpool rotation starts it should all start to gather in the bottom center of the keggle. There's plenty of real estate there for hop debris and trub.

Will test with 7.5 oz of pellet hops in a 5.5 gal pale ale if I can find the time to brew this weekend.

 

[Horseflesh]

I have a 5500W straight element and have settled on this routine: 100% to 207F, then I drop to 65%. This is for boiling a ~7.5 gal batch down to about 6 gal in 1 hour. (My first trial used 85% cruise power and that gave me a scorched spot on the element.)

My boil temperature barely exceeds 210F though, and I am at sea level. I can't figure that out. I even did all kinds of tests to make sure my system wasn't screwed up. Maybe there's a bug in the controller and at 65% power it is putting out less than 65% power... but at 100% power I get temperature changes as calculations forecast.

Then, I remembered they can still make beer in Denver where boiling is 203F and I stopped worrying about it.