Bunn Dual Voltage Models Starting at Serial #024477 CDBC - Manual (Page 13)

Page 13
TROUBLESHOOTING (cont.)
PROBLEM PROBABLE CAUSE REMEDY
HEATING CIRCUIT
1. Display flashing
2. Water not touching temperature
probe
3. Water Level Probe Sensing Sys-
tem
4. Temperature Probe
5. Limit Thermostat
Brewer has shut down due to mal-
function (See Diagnostic Chart in
manual, Page 20, or under top lid).
Remove temperature probe and
grommet. Look into hole on tank
lid. Water must be within one inch
from top of tank.
Disconnect the brewer from the
power source. Disconnect the J3
connector from the control board.
Check for continuity from the tank
mounting screw where the green
wire mounts, to pin 2 of the plug,
continuity should be present. Pull
the temperature probe up about an
inch from the grommet. Check for
continuity from the outside surface
of the temperature probe and pin 4
of the plug, continuity should be
present. Connect the J3 plug to the
control board and proceed to step
4.
Remove the probe from the grom-
met and submerge in a water bath
of approximately 70
°F(21°C). Con-
nect an ohmmeter to pins 3 and 4 of
the J3 connector. At 60
°F(16°C) the
reading should be 15.3k
± 2k OHMS,
at 70
°F(21°C) the reading should
be 11.8k ± 2k OHMS, and at
80 °F(27°C) the reading should be
9.3k
± 2k OHMS. If the probe is
within these parameters, reconnect
the J3 plug to the control board.
Disconnect the brewer from the
power source. Check for continuity
across the limit thermostat termi-
nals. Continuity should be present.
If not replace the limit thermostat.
(See page 25)
Water does not heat to proper tem-
perature
IMPORTANT: Make sure no tem-
perature tests are taken before the
ready light is "ON". Tank tempera-
ture must be stabilized before read-
ings are taken.
29707.1 082803