I have read as much as I can about both of these machines and aside from the addition of a steam PID, some body modifications (reinforcing group head, rounded corners, etc), some minor plumbing mods, I cant seem to find anything different in regards to what would influence pressure / temperature stability during extraction.

Are there any modifications made to the 2,3,4 Duetto's that would produce a better shot than on the original model? If so, what are they and is it possible to mod an original model to improve it?. I know the brew boiler increased size by .2L. Im not convinced a swap would be worth it even if it is possible.

I have purchased a Duetto 1. I plan on looking into adding the steam PID and a SS relay if possible. I also plan on machining out the top tray ventilate it better, adding boiler insulation to the steam boiler.

Are there any common problems with these machines? Any major drawbacks to the 1?

Ltrain5000 wrote:
1. Mods, I cant seem to find anything different in regards to what would influence pressure / temperature stability during extraction.

2. Are there any modifications made to the 2,3,4 Duetto's that would produce a better shot than on the original model? If so, what are they and is it possible to mod an original model to improve it?. I know the brew boiler increased size by .2L. Im not convinced a swap would be worth it even if it is possible.

3. I have purchased a Duetto 1. I plan on looking into adding the steam PID and a SS relay if possible. I also plan on machining out the top tray ventilate it better, adding boiler insulation to the steam boiler.

4. Are there any common problems with these machines? Any major drawbacks to the 1?

1. There is nothing that will affect these things

2. No...if the brew boiler increased in size, it was probably because of the manufacturer of the boilers, nothing else. it will make no difference to the shot.

3. Leave the existing PID and pressurestat, just add a solid state relay if the mechanical one ever fails. I assume yours has a steam boiler on/off switch, only models 0001 - 0020 didn't have a steam boiler on off switch.

4. Anti backflow valve will leak back if running tanked, using hard water...but an easy fix. Compression steam wands can be damaged by the ham fisted, but if gentle with them they will outlast no compression valves, before needing servicing. Pump should be lifted slightly off mounting and checked for leaks annually.

The PID can fail, but it's usually the onboard 12V hahn transformer that fails, you can fix it with bellwire and off board the transformer to an area above the pump, fix costs a few dollars. if you add a 50 ohm resistor (UK) at the same time, the PID will last much longer (your just looking to drop the voltage a tad).

As for mods, I have some ideas here for you

http://coffeetime.wikidot.com/izzo-alex ... erformance
http://coffeetime.wikidot.com/izzo-alex-duetto

The MK1 Duetto is a great machine, you really only need to fix it if it's broke, hence add the SSR when the Relay fails. Add a steam boiler on/off switch if you don't already have one. The steaming of the MK1 Duetto is better than the later models (benefit of pressurestat) especially the most recent MK1V...simply because the steam boiler shares the MK1Vs PID Brew boiler setting. Also the drip tray is much smaller. The MK1 also had lovely captive locknuts, not those threaded rivnut things the latest models have. Also on the MK1 you definitely have the preheat system I designed in the steam boiler...they may have mucked about with it on later models...I do know they made some changes to make it easier to build in the MK2 and beyond.

http://www.bellabarista.co.uk/pdf/Izzo- ... ook-v1.pdf

don't try and make it a MKIV, worst thing you could do, leave it as it is and enjoy, perhaps electronic low water detection and some protective mods (add an SSR only if the relay fails). I wouldn't change my MK1 to have MKIV features and I have number 0001 the pre production machine.!