Controlling evaporation on urn

[jackdaw]

I've modded my 40+ litre urn as it was cutting out at just over 100C when on flat out and taking ages for the thermostat to kick back in.

Now I manually turn it off for mashing (biab) at 66-68C and have it flat out rolling boil after removing the bag.

Problem is, with a 90min boil I'm losing too much liquid. 36 litres becomes 18l-20l + trubb.

Should I shorten my boil time or is there a way I (I mean a sparky) can modify the amount of power to the heating element?

Cheers,
Reg

 

[Bribie G]

Any reason you do a 90 min boil? I only do that with lagers (DMS etc) and even then it's probably unnecessary with modern malts.
How about just doing a 60 and topping up a few times with boiling electric kettle water?

 

[mxd]

A bit less power on the boil, a half on lid.

Shorter boil

 

[Bribie G]

He can't get a bit less power on the boil because he's modded the urn.

 

[jackdaw]

Cheers. Dont think the 1/2 lid on will work - boilover
Just done a brew starting with 36 litres and a 60 min boil (just whirlpooled) will see how it goes!

Cheers.

 

[DU99]

thermostat to kick back in

is a controller issue..calibration + or- ..what mods have you made to thermostat

 

[kevinj]

[SIZE=8pt]Someone on here said [/SIZE]

[SIZE=8pt]Calculations for how much water to add? i.e. [email protected] to [email protected][/SIZE]
[SIZE=9.5pt]The calculation works as such

C1V1 = C2V2

Where 'C' represents the concentration and 'V' represents the volume... so all we have to do is input our figures.

We know that C1 (our first concentration (or gravity of the wort)) is = 83 (rather than putting 1.083, just put the last 2 numbers)
We know that our initial volume (V1) = 12 (litres).
We know that our desired concentration (C2) = 48 (1.048, just use the last 2 numbers)
And the volume we want to know is V2.

C1V1 = C2V2
83 x 12 = 48 x ?
? = (83x12)/48
V2 = 20.75 (litres)[/SIZE]

 

[kevinj]

Found it! yay

The new StillDragon Controller kits are now in stock


DIY CONTROLLER KIT

 

[jackdaw]

is a controller issue..calibration + or- ..what mods have you made to thermostat

I put a silicon sleeve around the thermostat where it was in contact with the base of urn - I know now that 50C on the dial is around 65C actual and the silicon prevents cutout at 100C (obviously I'm using a thermometer too )