Originally Posted by winstonia
I wonder were you losing heat so quickly with the deadspace in the tun. I suspect this will be better when batch sparging etc
Could be. There was a good bit of space.
Right. I have done the test.
The boiler was started with the full 25 litres (up to the max mark) of water at 14.5C out of the cold tap
The temperature was measured at 5 minute intervals, necessitating opening the lid for about 30 seconds for each measurement. This was needed because of the time the thermometer takes to register the temperature.
The gain per five minute interval was as near as damn it 7 degrees C per 5 minutes or 1.4 degrees a minute. This was true all the way up to the upper end of the scale except that for some reason between minute 50 and 55, I only registered a gain of 5.5 degrees or 1.1 degrees per minute.
The full volume boiled at 64 minutes. At this point I noticed that my thermometer (Youngs Brewing Thermometer) is out by five degrees and was registering 105C.
So, in conclusion, the full volume of 25 litres reached mashing temperature at minute 35 - 37 (65C - 68C respectively).
It took 27 minutes to go from mash temperature (68C to boiling). Bear in mind that wort boils at a slightly higher temperature than 100C so would take a few minutes more.
Now - what do I do with all this boiling water?
I suppse I could monitor the cool down to properly evaluate the quality of the insulation. Maybe I'll measure the temperature every 15 minutes.....
By the way - the thermostat dial was bang on at 100c, cutting in at 97C and off again at 100. It is possible that my earlier remarks about the dial being off are really about my thermometer being off......
Can't wait to do my 23 litre stab at an AG mild with the remains of the Geterbrewed Real English IPA kit I won last week. I have already got a 9 litre IPA brew out of it that looks like coming in at 7%. That's a bit strong for my everyday dinner time pint, so I am doing the remains - 3.1kg grains and hops as a 23 litre brew that should come in about 3%. With a little hop tinkering, it should be bang on the style guide for Mild....... I have a keg ready and waiting for that one. Come next Tuesday the Cooper's 'Volcanic' Irish Stout should be done with the fermenter and I can start with the new boiler.