Need help to understand

After brewing my second batch in my new brew kettle, I decided to adjust the equipment profile of the pot to reflect what is actually happening.
I increased the boil off and cooling losses to match my actual results but also had to increase the loss to trub and chiller.
After making the changes to the pots profile, I applied the pot to the recipe that I had just brewed and was surprised to find that it did not affect the OG.
I understand that adding additional water to start the boil and then taking it out in the form of evaporation will leave me with a net no change in gravity.
The part I don't understand is the water that I added to account for trub loss. I assume that trub loss is simply wort that is left in the pot. That being the case, any water added to the start of the boil should in my mind dillute the wort and would require additional extract to keep the og at the target and that does not happen.

If anyone can explain this to me I would be grateful.

Thanks,
Jim

I've worked through this so hopefully this explanation will be helpful. It appears the calculators associated with Trub Loss are not taking into account the shift in OG resulting from increasing the boil volume. Sure; the Total Water Needed moves in lock-step with the Trub Loss adjustments, but that also results in a lower OG than estimated.

Assuming you're formulating a partial mash or all-grain recipe; look at the Mash Efficiency while you're adjusting the Trub Loss. Example; I adjust my Trub Loss from 0.40 to 0.80, my Mash Efficiency changes from 80% to 90%. All I did (I thought) was account for what actual trub losses I am seeing in my kettle, and it greatly increased my mash efficiency! But my OG was still way off the mark, so I dug deeper.

Knowing I wanted a certain amount in my fermenter, and knowing I was going to leave around 0.8 gallons in the kettle due to trub, I simply went back into my Equipment Profile and upped the Batch Size to account for the actual trub losses and this resulted in the sugars becoming part of the calculations that included the increased volume of water.

This work-around has provided me with exactly what I want in my fermenter in terms of volume, and I am nailing my OGs within a point or two every time! Give this a try and let me know how it works out for you. I find that I play around with the program to see what changes what, and this is all part of the brewing experience - always learning.

Thanks for the reply. It is good to know that I am not crazy.

I am extract not all grain but for my concerns, efficiency is not a concern.

I follow your logic for adjusting the batch volume in the equipment profile as a work-around and you are correct.

In playing with the changes, I found that if I increase the batch volume in the equipment profile, the bottling volume also increases by the same amount indicating a bottling volume that I won't actually get. However, if I increase the batch volume in the recipe and leave the batch volume alone in the equipment profile, I get the OG adjustment that is required and my equipment profile is reflecting actual conditions.

If I go your way and change the batch volume in the equipment profile, I need to remember for future batches that the bottling volume is wrong. If I go my way and change the batch volume in the recipe, I have to remember to change it for every future batch.

I guess the bottom line is : IT'S A WORK-AROUND!

I noticed this as well.  When its all said and done, I leave about 1 gal of trub and wort in the bottom of my boil kettle.  Since I want to put 5.5 gal of wort in the fermenter, I just up my batch size in the equipment profile to 6.5.  Now when I'm designing a recipe, I hit my actual OG numbers.  I noticed the discrepancy with the mash efficiency as well. At one point, BS calculated a 122% mash effiencincy for me.  That's when I started digging. I do the same thing that you do. I just have to remember to adjust the batch volume in the recipe.

This is the post I recomened that you read. Helped me understand how the calcs work in regards to equipment profiles.
http://www.beersmith.com/forum/index.php/topic,5140.0.html
Hope it helps.

Thank you Curly55.  I need to take more measurements, as I've only brewed 2 AG batches so far.