Bunn G1 Operating & Service Manual - page 18
18
Location:
The relay is located on the grinder base inside
the lower housing.
Test Procedure:
1.
Disconnect the grinder from the power source
and place a coffee bag behind the dispense chute.
2.
Check the voltage across the white/orange and
white or red/black wires on terminals A & B of
the relay with a voltmeter. Hold the Off/On/Start
switch in the “START” (lower) position and con-
nect the grinder to the power source. The indica-
tion must be:
a. 120 volts ac for two wire 120 volt models.
b. 230 volts ac for two wire 230 volt models.
c. 240 volts ac for two wire 240 volt models
3.
Disconnect the grinder from the power source.
If voltage is present as described, proceed to #4.
If voltage is not present as described, refer to the
Wiring Diagrams and check the grinder wiring har-
ness.
4.
Remove the white/red wires from relay contacts
7 & 9.
5.
Check the voltage across the white wire or red/
black on terminal B and either white/red wire with
a voltmeter. Place the Off/On/Start in either the
SERVICE (cont,)
“ON” (center) position or “START” (lower) posi-
tion. Connect the grinder to the power source.
The indication must be:
a. 120 volts ac for two wire 120 volt models.
b. 230 volts ac for two wire 230 volt 50 Hz mod-
els.
c. 240 volts ac for two wire 240 volt 60 Hz mod-
els.
6.
Disconnect the grinder from the power source.
7.
Check the voltage across terminal B and the re-
maining white/red wire with a voltmeter. Place
the Off/On/Start switch in either the “ON” (cen-
ter) position or “START (lower) position. Con-
nect the grinder to the power source. The indica-
tion must be:
a. 120 volts ac for two wire 120 volt models.
b. 230 volts ac for two wire 230 volt 50 Hz mod-
els.
c. 240 volts ac for two wire 240 volt 60 Hz mod-
els.
8.
Disconnect the grinder from the power source.
If voltage is present as described, proceed to #9.
If voltage is not present as described, refer to the Wir-
ing Diagrams and check the grinder wiring harness.
9.
Remove the white/violet wire from terminal 6 and
white/blue wire from terminal 4.
10. Check for continuity across terminals 7 & 4.
Connect the grinder to the power source.
Continuitymust be present when the Off/On/Start
switch is momentarily placed in the “START”
(lower) position and a bag is in place behind the
coffee dispense chute.
11. Check for continuity across terminals 9 & 6.
Connect the grinder to the power source. Conti-
nuity must be present when the Off/On/Start
switch is momentarily placed in the “START”
(lower) position and a bag is in place behind the
coffee dispense chute.
12. Disconnect the grinder from the power source.
If continuity is present as described, reconnect the
wires, the relay is operating properly.
If continuity is not present as described, replace the
relay.
RELAY
CLEA
NING
LEV
ER
CLEANING LEVER
GR
OUND
COFFEE
1. Select the desired grind.
2. Lift the lid and p
our coffee beans into the hopper.
3. Slip b
ag under the chute. Rest the bag on th
e tray.
4. Press the start switch.
5. Flip the cleaning lever a few
times as disp
ensing
slows.
6. Remove the b
ag. The grinder will stop au
tomatically.
ST
OP
TU
R
K
ISH
SP
EC
IA
L
R
E
G
P
E
R
C
E
L
E
C
P
E
R
C
A
U
TO
M
AT
IC
DRIP
FINE
ESP
RE
SS
O
FIG.14 RELAY
P1704
P1704