Reviving a really old thread here (sorry, but I can't justify opening a new thread just for this one topic): I came across a really old kit myself over the weekend. Well, two kits, actually. Both from Mangrove Jack, and I started brewing the first one (Bavarian Wheat). These kits must be around 4 years old, possibly more, and everything in them is "expired". The yeast has no date on it, but the extract tin it was shipped with was already "expired" in February 2016. So it's old. The "beer enhancer", basically the malt extract and dextrose mix expired around end 2017, so that was definitely still good.
Anyway, I mixed everything like the pack said I should and tossed it in the fermenter. Dropped temps down to 22°C (~72°F) by cold crashing the pot I used in freezing water. I also planned ahead by sanitizing the fermenter and going to the local water shop and filled it to 18l with purified water. The whole fermenter went into the chest freezer for a few hours before adding the wort, so the temps were quite low, which is good. I took the hydrometer reading and got it dead at 1.040, with the wort at 22°C. The hydrometer is calibrated at 20°C though, so the correction chart said to add 0.014 to the reading for every 2°C over the 20°C temp, so my original gravity is 1.054. Perfectly in range.
Back to topic though, I just pitched the dry yeast on top, mixed it in (making sure to splash a bit), topped up with purified water to the 23l mark and left it. next morning it was bubbling away, and 24h later I had a nice krauzen on the wort. The bubbling is slowly starting to die down now, around 72h later, which is on par with the ~5 days fermenting time recommended in the kit. Will take hydrometer readings in a few days to ensure it's stable before adding finings.
In this insane heat we're having (hitting 106°F felt temperature, like today), I've had to make a plan, so I tucked the fermenter in the back of a kitchen cabinet and packed the cabinet with ice packs (rotating them constantly). I am managing to keep the wort at a constant 22°C, with the 20°C block on the thermometer slightly lighting up, so I'm guessing my constant temp is sticking to 21°C~22°C, which is perfect for the yeast to not stress at all.
I'll report back on how it's going in a day or two.