Problem 11 - Shot volumes are consistently short..
Solution 1 - Replace the group valve plungers.
Each group valve has a plunger that is mechanically closed, preventing water flow to the group
head. The plunger is electromagnetically opened by the solenoid coil, allowing water flow to the
group. Over time, the rubber seat on the plunger becomes dried-out and/or cracked. When this
occurs, water, metered by the flowmeter, will actually discharge out of the bottom of the valve
into the drain box. If you notice water flowing from the discharge fitting in the drain box while
brewing, this is an indication that the group valve plungers require replacement.
1. Using a small phillips
screwdriver, remove the
main power switch knob.
2. Remove the 5 phillips
head screws that secure
the front panel and remove
the panel.
3. Remove the two
power leads going to the
coil.
4. Using a 14mm wrench,
remove the discharge nut
on the bottom of the valve.
5. Using a 13mm wrench,
remove the outlet fitting....
6...and the inlet fitting
from the group valve.
7. Gently manuever the valve
until it is free from the inlet
and outlet tubes.
8. Using a 14mm wrench, remove
the solenoid coil retaining nut and
coil from the valve stem.
9. Using a 22mm wrench,
remove the valve stem from
the valve body.
Important! - Before proceeding with solution 2, the following steps must be accom-
plished.
1. Turn off the main water supply to the machine.
2. Locate the expansion valve in the drain box.
3. Turn the barrel of the expansion valve counter-clockwise to releive pressure in the
front boiler.
4. When the lower portion of the gauge reads 0 bar, you may proceed.
