SAFETY CONTROLS
High Limit Switches (2)
(1) At heat exchanger (135°F/57°C)
(2) At heat exchanger outlet (150°F/65°C)
Water Pressure Switch
Prevents burner from firing if water flow
to the heater is restricted.
Air Flow Switch
Prevents igniter from firing if there is not
adequate vacuum in the blower.
Temperature Sensor
Controls heater operation to attain and
maintain selected water temperature.
Ignition Control
Provides pre-purge of the combustion
chamber. Opens the gas valve when the
igniter is hot enough. Monitors flame
condition so that unburned gas does
not escape.
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For detailed information, refer to the complete installation and owner’s manual.
