Bunn TU3Q - Manual (Page 16)

Page 16
SERVICE (cont.)
BREW TIMER (Early Models)
FIG. 4 BREW TIMER
P2088.50
Location:
The brew timer is located in the hood. It consists
of the dial plate and circuit board.
Test Procedure:
1. Disconnect the brewer from the power source.
2. Remove the wires from terminals TL3, TL4, & TL5
of the timer and rotate the dial fully counterclock-
wise.
3. With a voltmeter, check the voltage across termi-
nals TL1 and TL2 when the ON/OFF switch is in
the “ON” position. Connect the brewer 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 models.
c) 100 volts ac for two wire 100 volt models.
4. Disconnect the brewer from the power source.
If voltage is present as described, proceed to #5.
If voltage is not present as described, refer to the Wir-
ing Diagram and check the wiring harness.
5. Check for continuity across the white/orange and
white/yellow wires when the START switch is held
in the lower position.
If continuity is present as described, reconnect the
wires to terminals TL3, TL4, & TL5 of the timer board
and proceed to #6.
If continuity is not present as described, refer to the
Wiring Diagram and check the wiring harness.
6. With a voltmeter, check the voltage across termi-
nals TL1 and TL4 when the ON/OFF switch is in
the “ON” position and the START switch is mo-
mentarily placed in the lower position. Connect
the brewer to the power source. The indication
must be:
a) 120 volts ac for two wire 120 volt models for
approximately twenty seconds and then return
to its previous indication.
b) 230 volts ac for two wire 230 volt models for
approximately twenty seconds and then return to
is previous indication.
c) 100 volts ac for two wire 100 volt models for
approximately twenty seconds and then return to
its previous indication.
7. Disconnect the brewer from the power source.
If voltage is present as described, the timer is operat-
ing properly. Adjust the timer dial as required.
If voltage is not present as described, replace the timer.
Removal and Replacement:
1. Remove all wires from the timer.
2. Remove the circuit board and dial plate from the
brackets.
3. Install new timer circuit board as described in Late
Model Timer section on the following pages.
4. Refer to Fig. 7 when reconnecting the wires.
5. Install the Timer Setting decal, provided with the
replacement timer kit, to the rear of the schematic
beneath the top cover.
6. Adjust the timer as required. Refer to Late Model
Timer section on the following pages.
FIG. 5 BREW TIMER TERMINALS P2089.75
. MINUTES BUNN-O-MATIC P/N 2620- 120 VAC
OLD STYLE
10288 030201