The feed rate setting on Harman pellet stoves is based on a 60 second cycle. When the stove has a demand for heat based on your "Room Temp" setting of 74* and is 3* below the setpoint the stove will initially run the augar on a 60 second cycle, feed rate of 4 means the augar will run for 40 seconds, idle for 20 seconds. This cycle continues until the temp being registered by the room sensor approaches the temp setpoint on the stove, before the temp over shoots the target setpoint the circuit board over rides the initial feed cycle and starts to maintain the heat output by running the augar only to keep the room temp satisfied, this will vary within the 60 second cycle. When the room temp is satisfied the stove will run the augar approx. 7 seconds every minute to keep fuel in the burnpot. If you are running your stove in "Auto" with self ignition the stove will shutoff when it "CAN NOT" maintain a temp within 3* (77*)of your setpoint. Mostly on warmer days in the spring and fall. Having the feed rate set to low will not allow the stove to bring the room temp up in a reasonable amount of time, thus it will take much longer to achieve a setpoint with a feed rate of 2 because the augar will only cycle fuel for 20 seconds and sit idle for 40 seconds. You can potentially consume more fuel with a low feed rate setting, because you limit the max BTU output of the stove.