Harman Magnum Stoker, Operating Manual

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16
DO NOT BURN WET COAL
The purpose of having the off delay timer on the distribution blower is to exhaust the excess heat in
the stove that is inherent after the combustion blower and coal feeder turn off. For this reason, it is not
recommended that a 0 time setting be used. This will minimize any possibility of overheating the stove.
The other timer, which begins when the stoker control first takes control, is the "off" timer. This function
of the stoker control is adjustable from 0 minutes to 15 minutes. Programming this timer with a value lets
the stoker timer know how long to keep the combustion blower and the coal feeder turned off between
maintenance cycles.
Once the off timer has finished timing and the room temperature has not fallen below the thermostat
set point, the "on" timer function will begin. The programmable range for this function is also 0 minutes
to 15 minutes. Once the "on" timer has started, all output (combustion blower, distribution blower, coal
feeder) receptacles will become active for the programmed amount of time. When the "on" timer has
finished timing, the stoker control will recycle and the "distribution blower" timer along with the "off" timer
will once again become active.
The final operator interface is the switch on the
front panel adjacent to the receptacles. This switch
in the "on" position allows power to the coal feeder
motor receptacle. In the "off" position, power will be
removed only from the coal feeder motor receptacle.
This switch in the "off" position, will stop the coal from
moving across the grates and allow for easy lighting
of the fire. Once the fire has been established move
the switch to the "on" position.
how to Operate the Stoker Control
There are four operator interfaces on the stoker control.
The operator interfaces are one rocker switch and three,
16-position rotary switches.
The rocker switch is a power switch that controls only
the coal feeder motor. For normal operation, this switch
should be placed in the "on" position. This switch's
operation can be verified by a small red light above
the coal feeder receptacle being on when the switch
is on. If the stove needs to be shut down, simply place
the rocker switch in the "off" position. The small light
above the coal feeder receptacle will turn off.
The other three switches are the customer's
adjustments for the timers (on time, off time, distribution
blower time). These switches can adjust each timer
individually from 1 minute to 15 minutes in 1 minute
increments. Do not set timers to 0.
The "on" time and the "off" time should be programmed
to a minimum time that keeps the coal burning during
the maintenance cycling mode. The distribution blower
time should be programmed for a time which is long enough to move the excess heat from the stove to
the room heated. If this time is programmed for a longer time than the "off" time, the distribution blower
will operate continuously. This will have no damaging effect on the stoker control.
Recommended timer settings to start are, "on" 4 minutes, "off" 12 minutes, extend timer 2 minutes.
You may find that these settings produce too much heat in pilot mode. If so, you can reduce the "on"
time and increase the "off" time. However, be aware that you can go too far and have the fire go out. It
is best to make adjustments one minute at a time.