Post By Lukemc
NS Appia 2 - 2 group compact
I helped get hold of one of these for a customer of mine. They have it in a small town post office and go through about 7kg of coffee a week.
The double shot button on left and right group dispenses 75g of water consistently with no group head in.
Same grind, dose and tamp the left group dispenses 40g of espresso in 30 seconds. The right group 40g in 20-22 seconds.
Same precision baskets in each group (and I swapped group handles with same results).
Can anyone suggest why? And if there is a fix?
I'd be looking to flowmeters first....
Could they fail under “pressure” of the puck? I assumed (maybe wrongly!!) that if they dispensed the same amount with no puck they were doing their job!!
Originally Posted by Caffeinator
Is there a separate brew pressure adjustment for each group?
The hydraulic drawing on the NS website is a bit simplified and only shows one group solenoid, whereas the electrical drawing shows both. I imaging the Hx had a single path until it splits to the two solenoids for the two groups.
What happens if you pull both shots simultaneously? Must be something from the solenoid onwards in the second group. Sounds like the 3-way solenoid is opening a bit under pressure in the second group and letting half out the drain pipe, can you check if anything is coming out the drain pipe during the shot?
Shall attempt this next visit and report back.
Originally Posted by level3ninja
I did wonder if it was as simple as overuse of One group and lack
of back flushing causing a slight blockage on one group vs the other.