I have a Goodman Dependable Nintytwo furnace. The draft inducer motor comes on but the furncae does not light. The motor will run for long periods. It will kick off then kick back on and the furnace will light. The furnace is not consistent, sometime it lights and sometimes it does not. It has a new pressure switch and a pretty new draft motor. Can you tell me what I should check?

Take out the flame sensor and clean it with a piece of sand paper or emery cloth and put it back in and this should get sustained flame. The flame sensor is located just in front of one of the flame ports. It probably has a small metal bracket that is holding a ceramic holder about the diameter of a pencil. The actual sensor to clean is the metal tube coming out of the ceramic holder.

Take out the flame sensor and clean it with a piece of sand paper or emery cloth and put it back in and this should get sustained flame. The flame sensor is located just in front of one of the flame ports. It probably has a small metal bracket that is holding a ceramic holder about the diameter of a pencil. The actual sensor to clean is the metal tube coming out of the ceramic holder.