Issues with boil off rate

[DaveMur]

Hi folks,

Looking for a bit of advice after my weekend brew. On my last batch both heating elements burned out which led to me replacing them with identical elements.

Fast forward to this weekend and my Saison brew ended up missing gravity by about 0.016. I also ended up with an extra 3 litres (which even more disappointingly couldn't fit in my 11l carboy). I ran the numbers and OG ties in with the recipe as a 12l batch rather than the 9l batch I was aiming for.

My boil off rate has consistently been 7l per hour (this boil was 5) and only 2 things have changed, first is the element. Like I said that is a like for like replacement. Second I have a fermentation chamber now which was operating out of the same twin socket during the boil.

Is it possible the element isn't a effective? Could running the chamber at the same time cause this? Visibly the boil wasn't as vigorous but didn't really think about it at the time.

Edit - I realise the best way is to now run through a boil or 2 with just water to check the boil off rate. Thought I'd see if anyone had any ideas to save me from doing it.

Thanks
Dave

 

[kh54s10]

I don't know enough about electricity to determine if running the fermentation chamber would affect the boil. But I would say that changing the elements very likely could..

Not much help, is it?

 

[mongoose33]

The ferm chamber should make no difference.

Sounds like the new element is different.

 

[DaveMur]

Cheers, guess I'll need to run off a boil to check the rate.

 

[Genuine]

The Best way is to throw in a few gallons, boil for an hour at the same power and see how much goes. My issue is that I keep fidgeting with the power output percentage on my controller from 60-75%. I just need to stick to a number and let it do it's thing.

I'll probably do that this weekend while cleaning up my equipment.

 

[mabrungard]

7L per hour???? That's huge! Why are you boiling so hard? I used to boil at about 4 to 5 L/hr and I've cut that back to around 2L/hr with no ill effects. I boil for an hour, but I essentially simmer the wort covered for a half hour and then open the kettle for the last half hour to expel DMS. I'm running my electric heating at about 25% during the covered simmer and then have to increase it to around 42% to get a decent, but modest boil for the uncovered duration.

The need to boil long and hard is a myth. Pro's no longer boil that way and homebrewers shouldn't either.

 

[postalbunny]

Check your rate...also, not sure the environmental here; but the humidity and outside temp affects my boil off rate slightly. I usually check at 1/2 the boil time and make sure i'm on track; i'll adjust the boil up/down if i think i'm going to be off.

I prefer to overshoot slightly rather than undershoot... it's easy to add a little spring or distilled water to "liquor up" if you've over boiled but getting more concentrated wort after you're already added some additions changes the recipe.

 

[augiedoggy]

I'm interested in why both elements burned out? Its rare for them to burn out period let alone two at the same time? What type of elements? 120v or 240?

 

[augiedoggy]

7L per hour???? That's huge! Why are you boiling so hard? I used to boil at about 4 to 5 L/hr and I've cut that back to around 2L/hr with no ill effects. I boil for an hour, but I essentially simmer the wort covered for a half hour and then open the kettle for the last half hour to expel DMS. I'm running my electric heating at about 25% during the covered simmer and then have to increase it to around 42% to get a decent, but modest boil for the uncovered duration.

The need to boil long and hard is a myth. Pro's no longer boil that way and homebrewers shouldn't either.

not to mention I believe theres a difference in a vigorous boil in a steam jacketed (and insulated) kettle vs an electric element as far as watt density and the effects of the wort against the heating surface that would effect the color and flavor of the beer.

 

[aeviaanah]

I understand there’s no way to check the old broken element but a volt amp meter could confirm wattage to the element. I’ve noticed a decrease in wattage as element gets dirty

 

[augiedoggy]

I understand there’s no way to check the old broken element but a volt amp meter could confirm wattage to the element. I’ve noticed a decrease in wattage as element gets dirty

the contamination of the surface shouldn't have anything to do with the resistance and wattage of the element...
often times elements are slightly below their advertised max rating. for example I have a 4500w ripple that only puts out about 4050 watts and has since new. I have a couple 5500w elements which are much closer to5500w ranging from 5350-5500w.
they also fluctuate depending on the voltage they are receiving.. for example they put out more power at 120v than 110v so if a lot of stuff is drawing at the same time ,yes the output could suffer.

The fact that the OP is stating that hes running two elements out of the the same twin socket concerns me.. This sounds to me like they are 120v elements and he is running them both off a single 15a or possibly 20 amp circuit the boil kettle elements would each draw between 12-16amps realistically that left over 4-8 amps could be enough for the fermentation element depending on wattage but its not a good idea.

OP, you do have both boil kettle elements plugged into different circuits powered by different breakers right?

 

[Sparkncode]

I regularly see 10V variation on my 230V mains which is well within expected tollerance.

Usually cold days where more people run heaters or arround evening meal times it drops. I had a winter brew with less boil off than i expected where i was in the middle of the boil arround 530pm and the volts were about 10V low compared to my usual mid afternoon summer brews and i ended up increasing my boil pwm by 5% to compensate.

10V low on an element drawing 20A is 200W less heating so significant on a 4500W element i use.

 

[DaveMur]

the contamination of the surface shouldn't have anything to do with the resistance and wattage of the element...
often times elements are slightly below their advertised max rating. for example I have a 4500w ripple that only puts out about 4050 watts and has since new. I have a couple 5500w elements which are much closer to5500w ranging from 5350-5500w.
they also fluctuate depending on the voltage they are receiving.. for example they put out more power at 120v than 110v so if a lot of stuff is drawing at the same time ,yes the output could suffer.

The fact that the OP is stating that hes running two elements out of the the same twin socket concerns me.. This sounds to me like they are 120v elements and he is running them both off a single 15a or possibly 20 amp circuit the boil kettle elements would each draw between 12-16amps realistically that left over 4-8 amps could be enough for the fermentation element depending on wattage but its not a good idea.

OP, you do have both boil kettle elements plugged into different circuits powered by different breakers right?

Sorry, lost track of this. The elements are 240v putting out 2200w. The old elements had a bit of dirt on them, never cleaned them properly which is why I think they failed.

It is running off a dual 15A socket however I only ever use one element at a time as I only do 3 gal batches, the 2nd is in case of a failure. The other socket has the fermentation fridge running of it which is why I'm wondering if that is affecting the current it can draw?

 

[augiedoggy]

Sorry, lost track of this. The elements are 240v putting out 2200w. The old elements had a bit of dirt on them, never cleaned them properly which is why I think they failed.

It is running off a dual 15A socket however I only ever use one element at a time as I only do 3 gal batches, the 2nd is in case of a failure. The other socket has the fermentation fridge running of it which is why I'm wondering if that is affecting the current it can draw?

Just a head up I'm not sure how the wiring works in your country but if it was the states (Ive never seen a dual 15amp 240v receptical used in the US myself so not assuming its here) In the states that normally means 15amp max for everything combined on that circuit... The heater and fridge likely exceed that when both running at the same time. Also is that the only plug on that breaker? and are you sure other things like the lights arent on the same circuit... If so these things could pull your voltage down and cause the element power to decrease as you suspected.

 

[DaveMur]

Just a head up I'm not sure how the wiring works in your country but if it was the states (Ive never seen a dual 15amp 240v receptical used in the US myself so not assuming its here) In the states that normally means 15amp max for everything combined on that circuit... The heater and fridge likely exceed that when both running at the same time. Also is that the only plug on that breaker? and are you sure other things like the lights arent on the same circuit... If so these things could pull your voltage down and cause the element power to decrease as you suspected.

I'm in the UK, just double checked and it is 20A. The breaker is only for electrical sockets in the kitchen excluding hite goods, these are on a sperate breaker. The fridge itself is just a small under counter fridge, 85W and the heating element is 45W. Now that I'm done the fermentation I might turn it off to run another boil.