I've been watching videos of people preparing coffee in Moka pots on Youtube and one thing I noticed is that most people seem to initially leave the lid open. However, when I tried this the initial volume of water from the spout erupts out in both directions with such ferocity that it actually leaves the pot entirely and drenches the stove on either direction.
In every video I have seen they seem to have a nice gentle flow that merely dribbles out of the spout and falls down the spout into the chamber. My one is more like a volcano!
I have tried using a lower setting on the hob - there are 6 settings. At the very lowest (#1) it doesn't boil at all. At settings 3-6 I get a huge jet of water as described above. At setting #2 I get a smaller jet of water (that still shoots out of the pot) however on this setting the water seems to stop boiling up from the lower chamber leaving me with half a cup of coffee.
I realise that I can just do this with the lid down but I'm curious as to why this seems to happen. It's a single cup aluminium Moka pot which hadn't been used regularly for maybe a year until the last few weeks when I have been using it regularly. I took it apart earlier today and gave everything a good scrub. Still no difference.
I have tried with the coffee chamber, full, half-full and empty (so just boiling water). It doesn't matter - same result with all. I always fill the water up to just below the valve. I have tried with cold water and warm water. Does anyone have any idea what might be causing this behaviour?