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328767-001
SAFETY LOCKOUTS
This water heater has several lockout features designed
to prevent the heater from operating in unsafe conditions.
HIGH LIMIT CONTROLS (ENERGY CUT OFF)
Thermostat/Water Temperature
This feature is a part of the gas control valve/thermostat
(see Figure 1, item 10) and limits the maximum water
temperature. In the event of the water overheating, this
safety feature shuts off the fuel supply to the burner.
Blower High Limit Switch
This device is located on the blower (see Figure 5, item
45) and limits the maximum temperature of the blower.
If the blower temperature rises above the temperature
setting, the switch opens causing the heater to shut down.
The switch will auto reset once the temperature drops
suf
fi
ciently.
BLOWER AIR PRESSURE SWITCHES
The blower/heater is equiped with two air pressure
switches located in the junction box (see Figure 5, item
46 and item 49). These devices are connected in series
and monitor the air pressure produced by the blower. In
the event that the exhaust venting becomes blocked or
suf
fi
ciently restricted, the normally open (NO) air pressure
switch will shut down the heater. In the event that the
intake pipe becomes suf
fi
ciently blocked or restricted, the
normally closed (NC) air pressure switch will shut down
the heater.
