A while since I did this. So most comments from memory.
If you are not moderately literate on wiring things, and comfortable with wiring 240V machines (or whatever your local power is), then get help from someone knowledgeable. It is simple wiring, but high voltages can be a problem if you don’t get it right.
There’s only really a few main items required: PID (and box for it), temperature sensor, and solid state relay (SSR)
I purchased items for the PID of group heater from Auber, although for subsequent mods on other machines I just got them all from Aliexpress. Except perhaps I’d get from Auber the temperature sensor which screws into the place where the old group temperature sensor is located, so needs to be correct thread and sensor right. Although the item number below tells you what it is - a PT100 sensor and an M4 thread. You should find that on Aliexpress.
The items I purchased from Auber I had written down, which were:
- Small Box for 1512, and 1812, and 1813. Black color*** Item Number SBOXB
- Temperature sensor for Rancilio and Gaggia Espresso machine. Item Number PT100M4
- 5A AC SSR, Item Number SRDA5
- Universal 1/32 DIN PID Temperature Controller (SYL-1512A) Item Number SRDA5
Plus a rubber grommet, suitable wire, ideally with heat proof silicon outer, and some heat proof braid for covering the wiring.
My PID was located with double sided tape under the chassis behind the water tray.
Doesn’t require much disassembly - pull off the body work, which is a single piece from memory. Temperature sensor is behind the group, as are the heaters, and the wires for the heaters are readily accessible from there.
Get a good quality SSR, although for the 2 group heaters it probably isn’t that important - they don’t draw a lot of current (100W x 2 from memory). Cheap SSR’s usually work, but tend to die more frequently in my experience. Make sure the switching SSR voltage suits the voltage output from the PID, and the main relay can switch mains voltage.
For the PID, should be many that are much the same as the Auber one on Aliexpress. Just make sure you get one with auto-learning - makes initial settings a breeze. Also the same boxes Auber sells are there.
It’s a worthwhile upgrade. But get help if you are not comfortable you understand the required wiring.
Have fun. Update the group on how you go.
Dave