Water Does Not Heat At All
• Check to see if the water level in the tank is in contact with the water level probe. If not, see
Tank Does Not Fill
.
The water will not heat unless it is in contact with the probe.
• If the water heats, but is not hot enough, see
Water Not Hot Enough
.
• If
Ready to brew
appears on the display, but the water is not hot, check the resistance across the leads of the
temperature sensor. If the resistance is less than 10 k and the water is not hot, replace the temperature sensor.
If the sensor resistance is above 10 k when the water is cool, replace the universal control module (UCM).
If
Heating...
appears on the display, but the water is not hot, follow the steps below. The following steps are
performed with the rear toggle switch in the ON position.
1 Check for power across the terminals of the heating element(s). If power is being supplied, remove the wires
and check for an open heating element.
2 If there is no power to the element(s), trace the circuit back (using the ELECTRICAL SCHEMATIC) to the power
DPSEUPmOEPVUXIFSFQPXFSJTMPTU*GUIFSFJTQPXFSJOUPUIFUSJBDCVUOPUPVUTFFUIFGPMMPXJOHTUFQ
3 If there is power into a triac, but not out, check for power at the gate terminal. Also check the wire to A2 from
the UCM. If the connections are good and power is being supplied to the triac, but there is no voltage out
of A2, replace the triac. If power is not being supplied from the UCM, but
Heating...
appears on the display,
check the wiring from the UCM to the triac. If the wiring is OK, replace the UCM.
Water Too Hot (Boiling or Excessive Steaming)
1 If
Over Temp Sensor
or
Ready to Brew
appears on the display and the water is too hot, go to
Over Temp
Sensor Error Message
.
2 If the display reads
Heating
DPOTUBOUMZmSTUDIFDLUPNBLFTVSFUIBUUIFUFNQFSBUVSFTFOTPSJTBUUBDIFEUJHIUMZ
to the tank and that heat sink compound was used. A properly mounted sensor should have a resistance of
around 7 k when the water is hot. If not, replace the sensor.
3 Check to see if the universal control module (UCM) constantly has power output to the triac, regardless of the
resistance of the temperature sensor. If so, the UCM is probably bad.
4 If the UCM is working properly, check for a bad triac.
Over Temp Sensor Error Message
This error message indicates that the universal control module (UCM) has detected a water overheating problem.
The UCM is reading a water temperature in the tank above 210ºF (99°C). If the water temperature is too hot, but
Heating...
appears on the display, see
Water Too Hot
. Once the malfunction causing the error is corrected, the
error message must be cleared. To reset the brewer and return to normal operation, turn the toggle switch on the
back of the brewer to the OFF position for 5 seconds, then back on.
1 Check for power at the gate terminal on the triac. If there is no power at the triac gate terminal but the heating
elements are always on, replace the triac.
2 Turn off power to the brewer and allow water tank to cool. Once cool, turn power back on while monitoring the
triac gate voltage. During normal operation, power should be applied to the gate terminal, then drop to below
1 Vac. The universal control module (UCM) should be replaced if power is applied to the triac gate constantly
even though
Ready to brew
or
Over Temp Sensor
appears on the display.
3 If the UCM is operating normally, check for a false over-temp error caused by the temperature sensor. Check
the resistance across the leads of the temperature sensor. If the resistance is less than 10 k when the water is
cool, replace the temperature sensor.
TROUBLESHOOTING GUIDE
TG39
G3 BREWERS WITH TRIAC, TROUBLESHOOTING GUIDE-200F
011818A
IMPORTANT:
Before proceeding, make sure that the control panel temperature is adjusted to compensate
for higher elevations. The factory setting is 200°F (92°C). Reduce the temperature setting 2°F (1°C) for
every 1000 feet (300 m) of elevation above 4000 feet (1200 m).
