What does Intertherm code 7 Blinks mean?
Intertherm furnace code 7 Blinks means the control detected a low flame-sensor signal on the supported control family. Confirm the model number and diagnostic chart inside the furnace door before replacing parts.
What causes Intertherm code 7 Blinks?
- A dirty flame sensor
- Poor furnace grounding or reversed polarity
- Low gas pressure or an unstable burner flame
Can I troubleshoot Intertherm code 7 Blinks?
- Turn furnace power off and confirm its access panel is fully seated.
- Try one reset and note whether the burners light briefly before shutting off.
How much does Intertherm code 7 Blinks cost to fix?
A flame sensor cleaning or replacement typically costs between $100 and $400 nationally.
When should I call a technician?
Call a technician if flame drops out again; flame current and combustion should be measured.
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.