Mysterious miscellaneous losses

[bairdo]

At the beginning of yesterdays boil there was 30.7L in the boiler, at flame out (60min boil) there was 25L.

I attach a site gauge to the boiler and begin lautering (fly sparge) and stopped when the boiler had 30.7L in it. Closed the valve, emptied the site gauge and boil for 60 mins. At flame out I open the valve again to see how much boiled off, it read 25 which meant about 6L boiled off.

My system is Boiler > therminator > march pump > venturi aerator > fermenter.

I ended up 3L of trub in the boiler. I've previously measured the volume of the therminator, pump and tubing to be about 0.5L. And shinkage should be 1.2L based on 4% of 30.7L

So.. 25 - 3 - 1.2 - 0.5 = 20L. But I only ended up with 18L..

I splashed some at one point but less than a cup. Where the h*ll did the other 2L go??!!

My site gauge is a 1/2" blichman qc elbow and length of tube - just screws on the output valve. I checked its accuracy (again!) at the end of yesterdays session, its spot on.

The only thing I can think of is the markings on baby bath bucket I use for measuring are not accurate - I made the markings myself and I'm quite particular about accuracy - however no beer was involved.. maybe thats where I went wrong?!

What don't I know?

Inside the boiler.
http://cdn.homebrewtalk.com/images/1/6/7/0/6/6/img_1875_sml-61444.jpg

Pics from yesterday;

Mashing
http://cdn.homebrewtalk.com/images/1/6/7/0/6/6/img_2761-63966.jpg

Lautering
http://cdn.homebrewtalk.com/images/1/6/7/0/6/6/img_2764-63965.jpg

Boiler to fermenter
http://cdn.homebrewtalk.com/images/1/6/7/0/6/6/img_2767-63964.jpg

 

[acidrain]

The only thing I can think of is the markings on baby bath bucket I use for measuring are not accurate

This

 

[bairdo]

This

I hear ya and will be checking it at lunchtime - will report back.

 

[bairdo]

Yup inaccuracies probably explain it. I poured 10L from the bucket into my fermenter and it came up to 9ish.

So I've just finished re-marking both site gauges. Measured every 2L with electronic kitchen scales - and yes I checked its accuracy against another set I use for weighing hops.


Sent from my iPhone using Home Brew

 

[acidrain]

Nice!