In the SETUP menu, what are your settings? Please post them here.
You have a tri-burn stoker mechanism (one plug, one motor blowing combustion air under the grate and also moving the carpet to feed coal). You are saying that it is always running.
If you have TBRN set to N, then this should not be the case. Even at maximum MAX and FR there will always be at least 1 second out of 120 where the stoker will shut off. With MIN of 4 and MAX of 24, there should be significant stretches of time in each 120 second period where the stoker is off (115 seconds to 91 seconds, respectively). If you are in this mode and have MIN/MAX set like this, then you either have:
1) A bad speed control component on the stoker output: inside the control module box, usually only happens if the stoker motor stalls and causes an overload.
2) A badly wired control module box: rare, but it happens
3) You have the stoker motor plugged into the wrong receptacle on the box: we asked you to run through the TEST mode to make sure that the stoker motor only comes on when the STOKER display is on and off when any other display is up, to verify this.
If you have TBRN set to Y, then this can be the case. With MIN of 40 or higher and MAX of 99 then the stoker will always be running, but the speed of the motor will vary as FR goes from 0 to 99. You can tell if the speed control is working properly by counting how many times the carpet moves back and forth between being on the MIN screen and on the MAX screen. I'm not sure of the gearing reductions or motor speed, so you may not even make it through a full cycle in 120 seconds. Just pay attention to how far it moves if that is the case. Between a MIN of 40 and MAX of 99 there should be a significant difference. And again, it is important to verify that the motor is plugged into the correct receptacle and that there is no internal wiring problem (TEST mode will verify these situations). If you find that there is no difference in carpet movement between being on MIN screen and MAX screen and TEST mode works properly, then there may be a problem internally with the speed control components which will require service.