Bunn U3 U3A - Manual (Page 21)

Page 21
SERVICE (cont.)
LIQUID LEVEL BOARD AND LEVEL PROBE (cont.)
T1 BLU to Solenoid Valve
T2 BLK to ON/OFF Switch (All
models except 230V-CE models)
T3 WHI to Main Harness
(120/208V, 120/240V,
four wire 380V and 440V
models)
T3 WHI to Transformer
(380V three wire models)
T3 RED to Main Harness
(208V, 240V single phase
and three phase models)
T3 BLK to Main Harness
(230V two wire models)
T4 PIN to Level Probe
FIG.13 LIQUID LEVEL BOARD TERMINALS
P1733
9. Reconnect the pink wire to terminal 4.
10. Remove the two #8-32 screws securing the level
probe to the component bracket.
11. Gently pull the probe out of the component bracket
and inspect for corrosion. Replace if necessary.
12 Place the probe so that neither end is in contact
with any metal surface of the brewer.
13. Connect the brewer to the power source. Check
the voltage across terminals 1 and 3, refer to chart
below. There is an approximate delay of five sec-
onds for output to stabilize.
14. Disconnect the brewer from the power source.
If voltage is present as described, reinstall the level
probe, the liquid level board and level probe are
operating properly.
If voltage is not present as described, check the pink
wire on the level probe from liquid level board terminal
4.
Removal and Replacement:
1. Remove all wires from the liquid level board.
2. Remove the #10-32 screw and flat washer secur-
ing the protective shield to the component bracket.
3. Remove the #10-32 screw and internal tooth
lockwasher securing the liquid level board to the
component bracket.
4. Remove liquid level board and discard.
5. Install new liquid level board on component bracket
and secure with a #10-32 screw and internal tooth
lockwasher.
6. Install protective shield and secure with #10-32
screw and flat washer.
7. Refer to Fig. 13 and reconnect the wires.
Voltage -
Jumper
Not Touching
Frame
120V
230V
208V or
240V
220V or
254V
120V
Model
120/208V &
120/240V - 3
wire w/ground
single phase
230V - 2 wire
w/ground
single phase
208V or 240V -
2 wire wground
single phase
280V or 440V -
4 wire w/ground
3 phase
380V - 3 wire
w/ground 3
phase w/
stepdown trans-
former
Voltage -
Jumper
Touching
Frame
0
0
0
0
0
0
0
10060 080900