After living with the Rancilio Miss Silvia for 3 years, it is time to move on,
Most budding home Baristas start with a single boiler machine and live with the waiting for the steam, the flushing and the temperature surfing. This serves well for one or two cappachinos but when it comes to satisfying the thirst of multiple guests one hankers after something with simultaneous steaming and brewing.
This leaves you with 2 options and a tricky decision to make with the multitude of machines available to the home barista.
Option 1 - The Heat exchanger (HX)
A HX machine has a single boiler which serves to provide both steam and hot water, The steam is tapped off from the top of the boiler and the hot water (for tea/topping up americano's) is tapped of lower down in the boiler. The water to the group head is drawn up directly from the fresh (tank or mains) through the boiler which 'exchanges' or transfers the heat from the boiler on the fly and brings it up to brew temperature'
Pros; Cheaper than a DB, the brew water is fresher as it is drawn directly from the fresh supply
Cons; less stable brew temperature than a DB, requires cooling flush before brewing.
Option 2 - DB (Double Boiler)
A DB as the name suggests has a double boiler, one for hot water and steam and the other for the water to supply the group. This allows both to have independent thermostats or PID's to regulate the temperature.
Pros; More stable brew temperature for the group. No need for cooling flush
Cons; The brew water is not as fresh as it is drawn from inside a boiler which is subject to reboiling.
After weighing the odds I decided to go for a HX machine, The cost saving and the fact that the brew water is drawn from the fresh supply pleased to bee, especially as i typically only are 1-2 coffees a day in the week (more at the weekend!)
After much research I narrowed the choice down to an E61 machine, this is the name of the group head developed by Faema in the 1960's - you will notice on many espresso machine that sicks out of the from of the machine, and are normally super shiny Chrome. The advantage of the E61 is that it is kept hot by cycling hot water form the boiler and offers some pre-infusion by partially racing the lever. Apart from that it looks super sexy or as my wife says 'Tacky'...
More info here;
I narrowed the Espresso machines down to the Rocket Evoluzione v2 and the ECM Heidelburg Mechanika both around my Budget. After much deliberation I went for the Rocket, if I'm honest it is because it has always been the machine I hankered after and it looks so cool, specially the Giotto version with e coffin esau side panels.
Shiny - Ill post my thoughts once I have got to know my new machine
loves to grind&brew, talk about and drink coffee.