Bradford White ERE240 Service Manual page 6

INFORMATION
High Limit (ECO)/Upper Temperature Sensor
The surface mounted High Limit (Electrical Cut-Out) and Upper Temperature Sensor assembly is
mounted in the upper handhole of the water heater by a bracket which holds it against the side of
the tank.
The Upper Temperature Sensor and the High Limit (ECO) both respond to tank surface temperatures.
For the Upper Temperature sensor this means letting the controller know when to either call for heat
or when to indicate that the tank it satisfied. In the case of the High Limit (ECO) it cuts power to the
heating elements if the temperature exceeds a predetermined temperature (High Limit). It is important
that the entire back surface of the High Limit and temperature sensor are in full contact with or flush to
the surface of the tank. An improperly mounted High Limit (ECO) or Upper Temperature Sensor will
lead to improper water heater operation.
Power Switch Module
The surface mounted Power Switch Module is an assembly that consists of the lower temperature
sensor, and solid-state switches that control power to the heating elements. The Power Switch Module
receives signals from the Control Module to turn On/Off power to the upper and lower heating elements.
Temperature readings from the Power Switch Module are used by the Control Module to determine when
to turn On/Off the Heating Elements. The Power Switch Module is mounted in the lower handhole via a
spring clip and retaining lever. Good thermal contact from the Power Switch Module to the tank wall is
critical to the proper operation of the water heater. It is important that the tank wall is free of debris and
that an adequate layer of thermal paste is applied between the tank wall and the Power Switch Module.
Control Module
The Control Module, located in the plastic upper handhole cover, is the main circuit board in the ICON
E™ Electronic Control system. The Control Module does the thinking for the control system, reads the
temperature sensors, and controls the elements. It also reads the user setpoint temperature and
displays user notifications using an LED. It's important to make sure that the connectors are properly
connected to the Control Module to ensure proper operation.
Direct Immersion "Screw-in" Type Heating Element
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