Help needed: Grainfather losses

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Any help from experienced Grainfather users appreciated.

I have done 2 brews on my new G30 and love the kit but both times I have ended up with a lot less wort than expected. The first I put down to inexperience with the equipment but a repeat performance yesterday has got me questioning things.

Yesterday:
Aiming for 19L in the FM bucket

I had 16L in the mash for 4.6kg grain with 12L sparge = 28L total

Pre-Boil, I had about 24L in the kettle (based on markings inside the GF) which seemed about right for 19L wort. The GF settings are set at 3L boil off in 60 minutes + 2L trub/chiller.

I ended up with about 15.5L in the FV bucket so I lost 8.5L not 5L.

My measured kettle trub was 2.5L - add in 0.5L for chiller = 3L.

A further 0.5L could have been absorbed by the kettle hop pellets in a nylon bag.

That leaves 5L boil off which seems way too high.

I've checked the markings on the FM bucket and they are pretty accurate and certainly don't explain the discrepancy.

Anyone out there experienced anything similar or who can help me understand where the volume was lost?
 
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Any help from experienced Grainfather users appreciated.

I have done 2 brews on my new G30 and love the kit but both times I have ended up with a lot less wort than expected. The first I put down to inexperience with the equipment but a repeat performance yesterday has got me questioning things.

Yesterday:
Aiming for 19L in the FM bucket

I had 16L in the mash for 4.6kg grain with 12L sparge = 28L total

Pre-Boil, I had about 24L in the kettle (based on markings inside the GF) which seemed about right for 19L wort. The GF settings are set at 3L boil off in 60 minutes + 2L trub/chiller.

I ended up with about 15.5L in the FV bucket so I lost 8.5L not 5L.

My measured kettle trub was 2.5L - add in 0.5L for chiller = 3L.

A further 0.5L could have been absorbed by the kettle hop pellets in a nylon bag.

That leaves 5L boil off which seems way too high.

I've checked the markings on the FM bucket and they are pretty accurate and certainly don't explain the discrepancy.

Anyone out there experienced anything similar or who can help me understand where the volume was lost?
Sorry if this is an insulting question, but have you done a boil off test?

Basically boil off water for an hour, and how much do you lose?

Or 15mins and times it by 4

What is your power setting for the boil?
 
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Not an insulting question at all, OB. I haven't done a test. I was (rightly or wrongly) assuming the GF standard estimate would be more or less accurate.

The power is 220V. Though I have just discovered there is a way to manually control the power during the boil in the GF settings. Maybe I need to do that. The boil at 'full power' is certainly very vigorous.
 

Agentgonzo

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Do you have an insulating jacket (graincoat)? If so, less heat is lost through the body which will lead to more boil off. Without this, I got the 3L boil off that the grainfather says to expect. I haven't measured boil off with it, but I reduce my power now.

How many hops did you add? If it's a very hoppy American ale, the hops will absorb a lot of wort and increase your losses. Whole hops moreso than pellets.

Next time you brew, see what the boil off is by reading the volume in the kettle at the start of the boil (once the foam has died down) and then again at the end.
 

the baron

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I do not boil at full pelt as it will deffo increase a standard boil off of 3 litres by may upto double so I would say most of the discrepancy is there.
Either re-vist your boil off at full pelt or reduce the boil to be not as vigorous which would get you near the 3ltr boil off. Do not forget if you are sparging to the markings water expands and when cooled will be lower in volume markings in the kettle so that may be part of it too
 

Agentgonzo

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3L of boiloff (for a 24L boil) is also on the high side (12.5%). Guidance (which varies a lot) is anywhere between 6 and 10%
 

the baron

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Your boil off will be nearer the 4-5 ltrs especially if it is vigorous, your expansion loss will be approx 4% or a good ltr, 2.5 to trub loss .5 to chill loss, .5 to hop loss and you are getting nearer the mark. you said it was a vigorous boil on a electric system so 4+2,5+1+.5+.5=8.5ltrs.
Just to show you what is expected from a All In One System this is a lift from Brewers Friend re calculating your boil off
Amount of volume lost per hour during boil in quarts or liters. Typically 6 for wide kettles, and 4 for keggles. Electric elements tend to produce less. Also depends on how 'hard' you boil.
Ps only use your markings on the AIO system as a guide unless you have confirmed they are correct also if you do not forget the expansion amount of 1 ltr approx so 24 ltrs on the unit (even if correct)will be actually 23ltrs
 

Agentgonzo

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Your boil off will be nearer the 4-5 ltrs especially if it is vigorous
For 24L of pre-boil wort, 4-5 litres is way too much to boil off IMO (16-20%), but we've been through this to death in other threads 🤐. Grainfather G30 says to expect 3L boiloff for a 60 minute boil on full power.
 

the baron

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IMO its not, it depends whose figures you read and thats what I have found in my brewing experience too so we beg to differ ;)
 
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Any help from experienced Grainfather users appreciated.

I have done 2 brews on my new G30 and love the kit but both times I have ended up with a lot less wort than expected. The first I put down to inexperience with the equipment but a repeat performance yesterday has got me questioning things.

Yesterday:
Aiming for 19L in the FM bucket

I had 16L in the mash for 4.6kg grain with 12L sparge = 28L total

Pre-Boil, I had about 24L in the kettle (based on markings inside the GF) which seemed about right for 19L wort. The GF settings are set at 3L boil off in 60 minutes + 2L trub/chiller.

I ended up with about 15.5L in the FV bucket so I lost 8.5L not 5L.

My measured kettle trub was 2.5L - add in 0.5L for chiller = 3L.

A further 0.5L could have been absorbed by the kettle hop pellets in a nylon bag.

That leaves 5L boil off which seems way too high.

I've checked the markings on the FM bucket and they are pretty accurate and certainly don't explain the discrepancy.

Anyone out there experienced anything similar or who can help me understand where the volume was lost?
You don't mention your OG in your post, assuming that the losses are significant to your calculations your OG must be well over what is expected.
For my 40 litre Guten my boil off in 1 hour is 4 litres for the 70 litre it is 5 litres per hour which is in the ball park for a home brewer.
I did have a look at the Grainfather blog where they say 7% per hour in line with commercial breweries? Why I don't know, a commercial brewery loss to boil is around 7-% but they are more efficient than the home brewer who can expect around 15% loss.
I don't know if your markings are accurate on the GF, the Guten has the dead space subtracted from the markings so about 2 -2.5 litres out.
This article may help you understand.
 

Agentgonzo

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You don't mention your OG in your post, assuming that the losses are significant to your calculations your OG must be well over what is expected.
For my 40 litre Guten my boil off in 1 hour is 4 litres for the 70 litre it is 5 litres per hour which is in the ball park for a home brewer.
I did have a look at the Grainfather blog where they say 7% per hour in line with commercial breweries? Why I don't know, a commercial brewery loss to boil is around 7-% but they are more efficient than the home brewer who can expect around 15% loss.
I don't know if your markings are accurate on the GF, the Guten has the dead space subtracted from the markings so about 2 -2.5 litres out.
This article may help you understand.
I'm going to brew this weekend. I'll measure out litre jugs when filling it and see how accurate they are. I expect they are accurate enough and don't subtract the dead space.
 
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I'm going to brew this weekend. I'll measure out litre jugs when filling it and see how accurate they are. I expect they are accurate enough and don't subtract the dead space.
I have a feeling it is something unique to the Guten. I have made a dipstick and use that, also check your jug by weight to see if that is accurate, my 5 litre jug wasn't.
 

Agentgonzo

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We always weigh water when needing accuracy (baking etc) instead of using measuring jugs as the kitchen ones are "moderately" accurate. From memory it over reads by any 50ml. But good to mention it 👍 just to be safe. I only have a litre jug so it'll take a while...
 
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the baron

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Thanks @Agentgonzo and @the baron

Appreciate the input. I don't have an insulating jacket and it sounds like controlling the vigour of the boil is the obvious place to start.

I'll do a test boil off with water as @Obadiah Boondoggle suggested too.

I'm sure I'll get the hang of the equipment and how it works for me with a few more brews.
As you can see it is better to do a water boil off for yourself as it varies quite a lot and conflicting advice may be not so co flirting it is just different systems that boil off rates depend on the type of boil also some people have said they do by get much boil off and left the lid on in the past which also alters it too.

My most important advice is check your water quantities are correct and do not trust the markings as they are only a guideline
 

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I had similar challenges staring off and still not every brew can be treated the same.

In with @Obadiah Boondoggle , measure your losses. Take readings at every stage also when you next brew to identify where it could be going array.

I have found I achieve 3.3l/hr with my jacket on the G30, giving me a vigorous boil v GF preset 3l/hr.

Finally are you using the grain farther app water calculator?. This is still in Beta and strangely gives you different sparge and mash volumes that the manual calculator on GF website. I don't think it's big enought to account for all your variences, but equally don't assume it's one factor you need to change.
 

the baron

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Protofloc tablets have a dispersant in them, if you watch they fizz until dissipated or they are reasonably easy to crumble between your finger and thumb so do what suits yourself in your process athumb..
 

Agentgonzo

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Yep. The grainfather volume markings are pretty accurate. This was 18l (by weight, using my most accurate scales to measure out 1kg of water 18 times).

(If you're confused by the markings, the upside down 20 is a reflection of the 20 mark in the surface of the water!)
 

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Yep. The grainfather volume markings are pretty accurate. This was 18l (by weight, using my most accurate scales to measure out 1kg of water 18 times).

(If you're confused by the markings, the upside down 20 is a reflection of the 20 mark in the surface of the water!)
Thank you for doing that!
 

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Any help from experienced Grainfather users appreciated.

I have done 2 brews on my new G30 and love the kit but both times I have ended up with a lot less wort than expected. The first I put down to inexperience with the equipment but a repeat performance yesterday has got me questioning things.

Yesterday:
Aiming for 19L in the FM bucket

I had 16L in the mash for 4.6kg grain with 12L sparge = 28L total

Pre-Boil, I had about 24L in the kettle (based on markings inside the GF) which seemed about right for 19L wort. The GF settings are set at 3L boil off in 60 minutes + 2L trub/chiller.

I ended up with about 15.5L in the FV bucket so I lost 8.5L not 5L.

My measured kettle trub was 2.5L - add in 0.5L for chiller = 3L.

A further 0.5L could have been absorbed by the kettle hop pellets in a nylon bag.

That leaves 5L boil off which seems way too high.

I've checked the markings on the FM bucket and they are pretty accurate and certainly don't explain the discrepancy.

Anyone out there experienced anything similar or who can help me understand where the volume was lost?
While since I brewed but looking over old notes with a fairly standard grist and hop bill and 60min boiI i was needing total mash and sparge water of 31l to get 21 in the FV. So similar to you.
 

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