Synesso Espresso Machine Technical Manual page 33

Only Cold Water
Flows when Switch
is On
Only Hot Water
Flows when Switch
is On
Electronics All zones read LO
An individual zone
reads LO
An Individual Zone
Reads HI or Above
250° F and the Cor-
responding Tank is
Cooling
Tanks will Not Heat
to Full Temperature
Cold Zone
Technical Manual
● Turn the mix valve clockwise until it stops. This will cut off all cold water
flow. If no water flows with the mix valve off, the water control valve on
the hot side of the mix valve has failed.
● Check that the mix valve is not fully closed. A fully closed mix valve will
only allow steaming water out to the hot water tap.
● If the mix valve is open a full turn and a half and the water flow is still
steaming and sputtering, the water control valve on the cold side of the
mix valve has failed.
● Check to make sure the element breaker is ON. Zones will read LO
until the temperature in that zone reaches 175° F.
● Test the connections at the probe and display.
● Test thermal overload (over temperature) switch
● On machines built prior to 01-01-2011, Test the fuse for that zone. Test
continuity between the ends to check for a blown fuse. Test that voltage
from ground to the fuse reads 110v.
● [DISCONNECT POWER TO THE MACHINE FOR THIS TEST] Test
continuity from the heating element posts to ground, and the resistance
between the posts.
● If all these tests prove to be ok and the LED for the relay (on the power
board inside the electrical box) is ON, then the relay has failed.
● Test the connections to the probe
● Test probe for failure with ohm meter and compare reading to neighbor-
ing probe
● Clean dust and debris from electronics box. Take a soft brush (clean
paint brush) to loosen debris and use a small vacuum hose to remove
loose debris.
● Solid State Relays can fail in either the ON or Off position
TRAINED OR AUTHORIZED PERSONNEL ONLY:
● Relay has failed in the ON position: The heating elements will not turn
off and they will overheat to a point where the thermal overload switch will
trip and break the circuit to the element. With power ON, test for voltage
at the fuse:
■ If voltage is present and the LED at the control board is not lit, then the
relay has failed ON.
■ If voltage is not present: TURN THE POWER OFF TO THE MACHINE
and test element leads for continuity to ground and for resistance across
the leads.
● Relay has failed in the OFF position: Heating element turns off because
of lack of signal. No other parts should be affected. Remember, when
testing for voltage, the solid state relay requires some load to function. A
failed open heating element, a tripped switch or a failed fuse will make a
solid state relay appear to have failed or be OFF. If the LED at the relay is
ON and there is no power at the relay:
■ On machines built prior to 01-01-2011, Test the fuse
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