After some soul-searching, I came up with the following:
- The mash was sub-standard. I had mashed a little too cold and also didn't sparge properly. I reckon I'd left a ton of sugars in the mash tun and ended topping up the boil with water to make 23 litres. The OG was 1032, which is quite weedy.
- I didn't filter properly. I ended up transferring a right load of trub and shit into the FV, including bits of hop stalks.
- I didn't aerate the wort.
- I pitched the yeast in too hot. My cooling coil got the wort down from 100C to about 40C very quickly but then further reductions in temperature were getting exponentially harder. I lost patience and pitched the yeast in while the wort was probably still 35-40C.
Today, I set about making brew number three. I didn't follow a recipe but used what ingredients I had. I used more malt. 3kg Maris Otter, 1.8kg Lager malt, 450g Light Crystal and 250g Carapils. I had swapped the supplied filter in the mash tun for a homemade one I assembled, which had more surface area. I also made a sparging tool which sprinkled liquor into the tun for me while I was drawing off from underneath. It all worked very well and I filtered the runnings through a little sieve before they reached the boiler.
After the boil, I cooled the wort with the cooling coil right down to 30C, which took some time. I then transferred to the FV via a fine sieve and allowed the liquid to drop down, splashing in and aerating itself.
I then left the wort to cool while I cleaned the equipment up, which took an hour. I pitched in at about 25C and popped the FV in my lovely brew kitchen. (see below).
Considering that on my last attempt it had taken two days for the yeast to show any signs of activity, I was surprised to find this batch bubbling away after five minutes. The OG was 1052 and I am very confident that I have cut out loads of technique errors from last time.