MEDIUM URGENCY

Heil 7 Flashes - Limit Circuit Lockout

7 flashes

Limit circuit locked out after repeated trips.

Brand: Heil (Also covers Tempstar, Comfortmaker, Keeprite, ICP, Day & Night, Arcoaire) | Equipment: Gas Furnace

What This Code Means

7 flashes on Heil/Tempstar/Comfortmaker means the control has seen repeated limit switch trips (code 4) and entered hard lockout. The furnace will not retry until power is cycled.

Likely Causes (Ranked)

Most common

Persistent airflow restriction

What: Filter, vents, or blower issue causing repeated overheating.

How to check: Inspect filter, vents, blower.

Fix: Address airflow problem.

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Common

Failed limit switch

What: Switch fails open or trips falsely.

How to check: Tech tests resistance.

Fix: Replace switch.

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Diagnostic Steps

Cut power 60s to clear lockout
Address airflow (filter, vents)
Check blower operation
Replace limit switch if airflow is good
Call tech if persistent

Frequently Asked Questions

Difference between Heil 4 and 7 flashes?

4 = single limit trip; 7 = locked out after repeated trips. Same root cause, escalated.

How to reset?

Cut power 60s. Fix airflow or it returns.

Same on Tempstar?

Yes.

Related Heil Codes

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Need More Help?

Try our interactive symptom diagnostic tool or browse Heil parts.

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