orphanespresso wrote:Yes, I agree that in theory the thermosiphon does allow for some level of temp control, but I just don't see , read, or hear about these difficult temperature problems in non thermosiphon systems. I don't think there is a body of evidence that points to direct boiler contact groups leading to inferior shots or thermosiphon systems resulting in superior shots. If there is any argument to be made of one system vs another it is highly anecdotal in nature and user specific as in user preference vs any solid temperature data.
Go on Doug admit it, Barb has caught you sneaking around datalogging at 4am with a secret Scace device you have tucked away
Well you bring up some good points, that perhaps the magic of levers is not all temperature related. I've long held the belief that the lever groups nice even dispersion and the column of water extraction makes up for a lot. Oh and of course the spring extraction "profile". Ahh that word profile starts to grate after a while...
Back to the subject at hand, I reckon that there are different horses for courses. For intermittent use like we do in the office/home/workshop you would be able to get away with any group+boiler arrangement whereas in a commercial environment I personally would be looking at a set up that would lean towards a heat exchanger.
Anyway we all have enough machines I am sure one day we can put some data together. But somehow datalogging the lever ladies just seems like heresy.