Blower runs continuously with no heat; LED flashes 8 times repeatedly.

Safety: Turn off power and gas. If you see signs of severe overheating (scorched paint, melted wires), do not operate the furnace until inspected by a professional.

Steps:

• Locate all rollout and limit switches in the burner and heat exchanger area. Many Tappan models have small disc-type switches with two wires and sometimes a red reset button.
• Press the reset button on any manual reset rollout switches. If they immediately trip again on the next heat cycle, stop and call a technician—this indicates a serious combustion or venting problem.
• With power off, test each limit and rollout switch for continuity. Replace any that remain open at room temperature and do not reset.
• Inspect wiring between the switches and the control board for burns or breaks. Repair or replace damaged wires with high-temperature-rated wire.
• After replacing any faulty switches and correcting underlying causes (such as blocked vent or dirty burners), restore power and test operation.