Threw in the grist at 70 and it dropped to about 65. Tried to warm up the heater and also threw in 2litres of hot water, the water might not have been hot enough (mistake) and it was mashing at 62 for quite some time. Suddenly the thermometer was showing 78 after about 20 minutes and I had to throw in 2 litres more of cold water. Mash was a totaly scandal.
Had calculated 15l of water and the grains to absorb 3l, they actually absorbed about 4. With 4l of more water thrown in I was now at 15 again. Threw in 6 more litres after the mash and started boiling (should have been 7 or 8 now when I think of it. I boiled off 4 litres of water during the boil.
Also maybe 2 litres of trub so ended up with just a bit more than 15 litres.