Furnace does not start at all; no fan, no clicking, no display or indicator lights

Safety: Turn off power at the breaker before removing any covers. Only work on mains wiring if you are competent and allowed to do so.

Steps:

• Check breaker and switch: Confirm the furnace breaker is ON and that any local isolation switch near the Ideal furnace is also ON.
• Door switch: Ensure the blower door is properly fitted and pressing the door safety switch; some furnaces will not power up if the door is loose.
• Internal fuse: With power off, remove the blower door and locate the small automotive-style fuse on the control board. If blown, replace with the same rating. If it blows again, there is a short that needs professional diagnosis.
• Call a technician: If power is present but the control board remains dead, the board or transformer may need replacement.