Well, I’ve been away from here for an embarrassingly long time again...
After 9 years with my Isomac Rituale I've decided it is time to seek a replacement. Not that the Rituale is on its last legs but it does get a lot of use and maybe something newer and more robust in due. Plus I would like to be able to plumb in the machine properly at some point and this is not really practical with the Rituale. Also I have a hankering for a rotary pump!
Within my budget I am pretty much looking at another E61 machine or possibly an S1 Vivaldi (though I am not a fan of the look of that one to be honest), but the big question is should I go for another heat exchanger machine or a dual boiler? In some ways I am tempted towards a dual boiler just because it is different to what I have, but that is not a particularly good reason for choosing...
I have been using one of Eric Svenson's E61 adapter with a digital thermometer for about 18 months to accurately get my required brew water temperature so I am happy that you can relatively easily recreate (and alter) brew temperature for different beans. However I do find that the process can still sometimes be tricky as my group idle temperature (prior to flushing) can vary by up to 5C which does change the temperature that you need to flush down to for recovery back to brew temp by the time you are ready to pull a shot. I don't know though whether this is just a quirk of the Isomac thermosyphon or common to E61 HX machines.
A dual boiler would have the advantage of more easily repeatable shot temperature and less process to get there but not so easy to change the brew temperature quickly as most (even with a PID) need 15 minutes or more to stabilise. I guess it depends if you brew several shots quickly at different temps to dial in a bean/blend or not. I do but not very often, Usually I will do it over a couple of days (not very scientifically controlled I know) as I don't do well drinking multiple shots in a row!
Primarily form a new machine I want:
More robust design & build
Temperature stability
Quieter (hence the rotary pump)
Prettier
Ease of getting spare parts
Easier maintenance e.g. boiler drains for easier descaling
As I live in a pretty hard water area that last one is quite am major one, the ease of descaling is paramount.
Anyone got any advice/experiences?
Simon