THERMOSTAT ADJUSTMENT
• Before adjusting the thermostats, make sure that the temperature
display probes and the thermostat probes are properly set in their
respective cavities.
• Check the exploded view for the model you are servicing to determine
the location of the thermostats.
• When the machine is ON and the wash tank is full, power is sent to the
booster thermostat. When the correct rinse water temperature is
achieved, power is transferred to the wash tank thermostat. When the
correct wash water temperature is achieved, power is transmitted to the READY indicator light on the control panel. The booster
always has priority in this sequence.
IMPORTANT NOTE:
When the booster element is heating, there will be no power going to the tank element. The two
elements are never on at the same time. If neither element is heating, check the booster contactor. If the booster element is
defective, the wash tank element will not heat.
• The thermostat that controls the booster is identified as "TB" and the thermostat that controls the wash tank element is
identified as "TV". The adjustment screw is in the middle of the thermostat and is sealed with paint to keep its calibration during
shipment. It is possible to break this seal by turning the adjustment screw with a flat bladed screwdriver. Adjustments should be
made in 1/8 of a turn increments, clockwise to increase the temperature and counter clockwise to decrease the temperature. You
should allow 10-15 minutes between adjustments for the temperature to stabilize. Listen carefully when adjusting the booster
thermostat. If you hear the water starting to boil in the booster tank, the thermostat is adjusted too high.
• Thermostat tolerance is ± 3 degrees:
140° F (60° C) for the wash.
185° F (85° C) for the rinse.
NOTE:
Several models have the thermostats located in the "Slide Out" control panel. Do not pull the drawer out so far as to pull
the air pressure hose off the air pressure switch.
F16 & F16 DP F20-F22-727-737-747
F18 & F18 DP
(Base of machine)
(Control Panel Top of machine)
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