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SAFETY DEVICES
1. High Limit Switch - The high limit switch is an ‘overheat’ safety switch that will shut off the fuel feed if the stove
reaches a temperature above the normal operating temperature. This switch is a manual reset type. There
is no diagnostic light associated with this switch. If this switch shuts the stove down, the control board will be
in ‘Internal Alarm’. The auger will stop turning and the #3 LED button will start blinking. When the high limit
switch causes a shutdown, the problem in the stove must be diagnosed before the stove is put back in
operation, but is almost always caused by a convection fan malfunction.
2. Proof of Fire Switch - The proof of fire switch is also called the P.O.F. This senses the temperature rise in the
exhaust system. This is a normally open type switch and closes the circuit at 110
o
F. The stove will shut down
if temperatures above 110
o
F are not sensed during start up or drops below 90
o
F during normal operation.
3. Vacuum Switch - This is sometimes referred to as the ‘Negative Pressure’ switch. When the stove is turned ‘ON’,
the exhaust fan creates a negative pressure inside the firebox. The control board continuously checks to see
that negative pressure is present during operation of the stove. If the exhaust vent system becomes clogged
and obstructed or the firebox door or ash door are left open or the fan quits working, the control board will go
into ‘Safety shutdown’. There is a 45 second delay before the stove shuts down. This is ample time to perform
daily maintenance.
4. Interlock Safety Switch -
An interlock safety switch is located on the top flange of the hopper. If the hopper lid
is opened, the interlock safety switch deactivates the auger. This switch has been installed to prevent fingers
from becoming caught in the auger and should never be disconnected for any reason.
Interlock Safety Switch
High Limit Switch
Vacuum Switch
Convection Fan
Terminal
Block
Proof of Fire Switch
Combustion Fan
View of back of stove
with hopper removed.
