Why do I lose so much water after boil?

[jampot]

Did my 4th ag today. My ag3 came up too short for water by 3 ltrs. Yikes I thought, must get it right next brew. Well today it got worse I had 31 liters of wort prior to the boil. My boiler has a dead space of 2.3 liters. Lets say 300 ml for the hops. That takes me down to 28.4 liters. Then 10-15% for the boil. So why did I end with 18 liters?

 

[keith1664]

Unless you're being very tight with the hops you'll be losing more than 300ml, I've seen a figure of 6 litres / kg mentioned on another site, but I'd put my losses higher than that. Also remember that you lose 10% when you cool to pitching temp.

 

[Runwell-Steve]

I work on a loss of 1.5 litres per 100g of hops. Seems about right for me.

I only have 0.5 litre dead space in my boiler though. If you are losing 2 litres to dead space you either need to redesign your hop filter or extend your outlet so it syphons properly.

 

[jampot]

Hi, yesterday I needed 56g of hops. I use a buffalo boiler. If I fill with just water and open the tap to release it until the water stops it will 2.3 liters so that's a guide.
Here is the hop filter I have....
http://cgi.ebay.co.uk/Viking-Hop-Filter ... 35b2d21ee8


How much do you factor in for loss to the boil? I lost a total of 13 liters here somewhere

 

[BigYin]

I think I see your problem. The strainer is fitted directly at the back of the tap, so there is no syphon effect possible once the liquid drops below the tap level.

My strainer sits on the floor of my boiler, and 'solid' pipe connects it to the tap above it. that ensures a syphon effect that continues until the liquid drops low enough to allow air to enter the strainer. Result : 200ml dead space :thumb:

Just connect your strainer to the tap with a couple of 90 degree elbows and a short length of 15mm tube, that way you'll get the syphon effect until the liquid gets low enough to expose the strainer.

 

[jampot]

I am not really a diy kinda guy hence buying the strainer. Could you link me to the bits I need. However, wouldn't the coil around the filter push the it up away from the bottom of the boiler ?

 

[BigYin]

the elbows are something like this : http://www.screwfix.com/p/elbow-15mm-pack-of-25/26265

and a small length of 15mm tube : http://www.screwfix.com/p/copper-tube-1 ... f-10/31854 - obviously not in THAT quantity!!

You don't need to worry about soldering them up - best not to in fact so you can pull them apart for cleaning :thumb:

You are right about the coil around the strainer - I take it that's to hold the mesh bag clear of the pipe? I'd be tempted to flatten it a little to get the pipe closer to the bottom :hmm:

 

[jampot]

Thanks, you can push the elbow onto a the thread of the thread of the tap? The strainer screws on properly with a kind of moving nut that tightens but still allows you to rotate the strainer so the dipped end can be positioned to create a siphon effect.... No idea where the tubing would go. Maybe you have picture of the idea?

 

[BigYin]

hmmmm - not so sure about the connection to the back of the tap :hmm:

On mine it's a 15mm 'tank connector' and I have 15mm copper tube coming through it into the boiler, and the 15mm elbow just pushes onto that. I doubt an elbow would push onto a screw thread :hmm:

Bound to be a way to solve it, I'm just not certain how.....

 

[jampot]

Putting the lost of about 3 liters to one side I still cant account for the other missing volume. How much on average do you lose to the boil?

 

[Moley]

I usually lose about 6 litres over a 90 minute boil. Obviously, this will vary according to the diameter of your boiler and how vigorously you get it rolling.

You can put it back though, get the kettle on and add a few scrapings of a CT to the water.

 

[Aleman]

I take it you are assuming :whistle: :whistle: that you are loosing 10-15% to the boil? Unless you actually measure this I think you are way underestimating the amount you loose . . . with an uncontrolled 3KW element you are probably looking at more like 25-30% . . . per hour

Loss to hops is 15L per kilo so 500ml per 50g is about right.

Measure your dead space . . .Put 10L in the boiler and then allow it to drain . . .tip out what's left . . .thats dead space, my 150L boiler with the tap at the 20L point has a dead space of 750ml if I drain the final 5L slowly due to the syphon effect.

 

[jampot]

Thanks for all replies, my dead space is 2.3 liters mentioned above. Its a 2.7kw buffalo boiler. It has a temp setting up to 110 degs. To get a constant rolling boil 110 is whats needed. If you try to turn it down a bit then thermostat kicks in and the rolling boil stops then comes back again pulsing between the two. Maybe this is a happy medium.? The diameter of the boiler is 15 inches.

 

[jampot]

This thread has gone a bit quiet, anyone else prepared to chip in re my last post?

 

[jez]

I think I have the same boiler as you. When I started using mine I lost more than I did with my old plastic boiler. I keep the boiler on 110 to get a nice rolling boil.

Simply add a few litres to your sparge water to accomodate.

 

[jampot]

Thanks, at what point I start to get the dredded off flavours etc

 

[Aleman]

Simply add a few litres to your sparge water to accomodate.

Or if you have reached your desired pre boil gravity top it up with boiling water from a kettle

If it is the power of the boiler (and I have a 3KW 38L electric boiler) then a thermostat is no good . . .you need it to boil at slightly more than 100C, but you need to turn the power of the element down. As I've posted before (And so I don't have to look up the links) a Burst Fire Controller or a Phase Angle Regulator is the way to go do do this . . . I fitted a Phase Angle Controller (With Big Heat Sink) to mine, and can control the boil from a gentle simmer up to wort jumping out of the top

 

[31bb3]

I generally sparge 7 litres more than my required final volume then tend to hit the amount i require

 

[jampot]

Simply add a few litres to your sparge water to accomodate.

Or if you have reached your desired pre boil gravity top it up with boiling water from a kettle

If it is the power of the boiler (and I have a 3KW 38L electric boiler) then a thermostat is no good . . .you need it to boil at slightly more than 100C, but you need to turn the power of the element down. As I've posted before (And so I don't have to look up the links) a Burst Fire Controller or a Phase Angle Regulator is the way to go do do this . . . I fitted a Phase Angle Controller (With Big Heat Sink) to mine, and can control the boil from a gentle simmer up to wort jumping out of the top

A bit out of my league I think. How you know your desired pre boil gravity?