What does Intertherm code 8 Blinks mean?
Intertherm furnace code 8 Blinks means the igniter relay reported a fault on the supported control family. Confirm the model number and diagnostic chart inside the furnace door before replacing parts.
What causes Intertherm code 8 Blinks?
- A cracked or open hot-surface igniter
- Loose or damaged igniter wiring
- A failed igniter relay on the control board
Can I troubleshoot Intertherm code 8 Blinks?
- Turn power off and look through the burner-viewing area for an obviously cracked igniter without touching it.
- Restore power once and observe whether the igniter glows; do not continue resetting the furnace.
How much does Intertherm code 8 Blinks cost to fix?
A furnace ignitor replacement typically costs between $150 and $500 nationally.
When should I call a technician?
Call a technician if the igniter does not glow or the fault returns.
Sources and model scope
Fault codes vary by model and control board. Confirm the diagnostic chart inside your furnace panel or the official manual before acting.
Scope used here: Nortek single-stage condensing furnaces using the documented Emerson integrated control.
- Nortek Global HVAC: Single Stage Condensing Gas Furnaces — Installation Instructions
1041594D · Nortek single-stage condensing gas furnaces using the documented Emerson integrated control; manufactured-home models and older boards may differ.
Compiled by Warmlo Editorial · Reviewed August 2026
This is general information, not professional advice. Gas, electrical, and combustion repairs can be dangerous — when in doubt, call a licensed technician.