MediumRoastSteam I might, but it just isn’t making sense. I am also learning a lot about how my machine works - to say I am starting from a position of complete ignorance is an understatement. So I will be all the better for the experience.
Water produces steam at 99/100 degC at standard atmospheric pressure (please correct me if I am wrong). As pressure increases, the temperature required for water to produce steam increases.
So if I am getting hot (let’s put my potentially erroneous and confusing temp reading to one side for the moment) spluttery water out of the hot water tap and steam out of the steam wand, it has got to be above 99/100 degC. If the VB closes at very low pressure, then the temp of the water has to be above this to continue to produce steam.
How much above is one question. The temp display might say 130degC, but it could be anywhere between 100 and 130. So I am going to be testing that by swapping the temp sensors.
What I have never done (and will do once all this is resolved) is test the steam power at say 110 and 120degC to see what the impact on the steam power is and affect on milk. At the moment it takes me 15-20s to pass the LH MJ test, which doesn’t seem too long, so if the steam is hot is there then a question around the pressure it is coming out of the steam wand?
My question on the VB stems from the amount of pressure required to close it. If opening the steam wand leads to a drop in pressure in the SB (which I am assuming it must) then can this theoretically lead to the VB opening? If it can, then would this lead to a drop in steam pressure but still allow the steam to heat the milk to the ‘correct’ temperature.
