This is the model without the abc buttons. Worked great last season. Cleaned and maintained checked no chimney blockage seems to be functioning properly and no error codes. Will not put out any heat. Room it is in should be 80 degrees can't get it above 50. Even running on highest settings hr9 df6 does the same wether in manual mode or auto. Damper all the way out or out 1 inch. Only time there's any change is close damper all the way fire goes out. Please help have no heat. Any suggestions. Burning pellets.