Synesso Espresso Machine, Technical Manual

Page: 29 / 62

Technical Manual 29
Category Symptom Possible Reasons and Solutions
Brew Pres-
sure or
Flow
Brew Gauge Reads
11 to 12 Bar when
Machine is Not
Brewing
● This is normal. When the brew tanks heat, the water expands and the
expansion valve is set to relieve excess water pressure at 11 to 12 Bar.
Brew Pressure is
Low
● [SINGLE INLET MACHINES ONLY] see “Brew pressure drops when
steam tank fills” below
● [SINGLE PUMP MACHINES ONLY] When brewing on one group and
another group is activated some water will be diverted to the second (or
third) group. This will slightly reduce available brew pressure.
● Expansion valve may be set too loose. Check that the pressure in the
brew system reaches 10-12 bar while heating from a cold state. If the
pressure does not exceed brew pressure, the expansion valve will need
to be tightened, cleaned, or rebuilt.
● Check pump to make sure pressure is properly set.
● Water supply hose to the pump may be kinked
● Water filter may be plugged. Check and replace if necessary
Brew Pressure
drops when Steam
Tank fills (SINGLE
INLET MACHINE
ONLY)
● This is common to all single inlet espresso machines. The water source
is the same for the steam and brew tanks. The pump is configured for a
set amount of pressure and when the steam tank fills, it diverts water and
pressure away from the brewing process and into the steam tank. If this is
an unacceptable situation, there are a few things you can do to minimize
or eliminate the pressure drop.
● There is an auto fill probe delay setting in the programming that is set
at the factory to 5 seconds. This means that the auto fill probe waits to
fill until it senses a continuous signal to fill for 5 seconds, and it does not
stop filling until is senses a continuous signal to stop filling for 5 seconds.
This stops the auto fill valve from turning off and on if the water in the
steam tank is making intermittent contact with the probe (due to internal
water movement).
● Minimize: Increase your auto fill probe delay setting to 10 seconds.
This will reduce the number of times that your steam tank fills. It will also
increase the fill time each time the valve opens. The water level in the
steam tank will vary more.
● Eliminate: If you can provide 2 separate sources of water (a steam tank
source and source run through the pump for brewing), it is possible to
custom plumb your machine so that this issue is eliminated. This takes
time, skill and extra parts. All machines made in 2008 and after have this
dual inlet system as a standard feature. Retrofit kits are available, check
with your dealer, service provider, or the Synesso factory for more infor-
mation about this upgrade.
No Brew Pressure,
Pump Motor is Run-
ning
● Failed pump, needs to be replaced
● The line between the pump and the water supply may be collapsed or
kinked.
TROUBLESHOOTING