MEDIUM URGENCY

Nordyne 3 Flashes - Limit Switch Open

3 flashes

High limit switch open - overheating. Usually restricted airflow.

Brand: Nordyne (Also covers Frigidaire, Maytag, Westinghouse, Tappan, Gibson, Intertherm, NuTone, Miller, Broan) | Equipment: Gas Furnace

What This Code Means

3 flashes on Nordyne-family furnaces means the high limit switch has tripped due to overheating in the heat exchanger.

Likely Causes (Ranked)

Most common (~70%)

Dirty air filter

What: Restricted airflow lets heat build up.

How to check: Inspect filter.

Fix: Replace filter, cycle power.

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Common

Closed registers

What: Static pressure spike from too many closed vents.

How to check: Open all vents.

Fix: Clear vents and returns.

Common

Failed blower

What: Weak blower can't carry heat away.

How to check: Feel airflow at register.

Fix: Test capacitor, replace motor.

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Diagnostic Steps

Cut power 30s
Replace filter
Open all vents
Wait for cooldown
Watch for code return

Frequently Asked Questions

Why does Nordyne 3 flashes keep coming?

Furnace overheating. Filter resolves most cases.

Same on Maytag/Westinghouse?

Yes.

DIY?

Filter and vents yes.

Related Nordyne Codes

Related Symptoms

Need More Help?

Try our interactive symptom diagnostic tool or browse Nordyne parts.

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