Bryant Furnace Error Codes 2026 (13, 31, 33 & Yellow Light Blinking)

You wake up freezing in the middle of the night. The vents are blowing cold air. The house is getting colder every minute.

You walk to your furnace and see a blinking light through the small window.

It might look like a random warning.

It’s not.

Your system is in a fault or safety lockout state, and that blinking light is the only way it can tell you what went wrong.

If you understand how to read it, you can diagnose the problem fast and often fix it without replacing expensive parts.

How to Read Bryant Codes Correctly

Bryant furnaces use a two-digit flash system:

• Short flashes = first number
• Long flashes = second number

Example:

• 3 short + 1 long → Code 31
• 3 short + 3 long → Code 33

Always check the code through the viewing window first.
Removing the panel cuts power and may reset the display.

What Does a Yellow Blinking Light Mean?

If you see a yellow (amber) blinking light, this is normal.

The color itself is NOT the problem.

What Actually Matters

• The LED color stays the same
• The flash pattern carries the meaning

Normal Yellow Light Behavior

• Slow steady blinking – standby
• Fast steady blinking – call for heat

No issue in these cases.

When Yellow Blinking Indicates a Problem

If the light flashes in a pattern:

• 3 short + 1 long = Code 31
• 3 short + 3 long = Code 33

That pattern is a fault condition.

Key Rule

If you see a yellow blinking light:

1. Ignore the color
2. Count the flashes
3. Identify the code
4. Diagnose the condition

When to Act Immediately

• no heat
• system shuts off repeatedly
• temperature keeps dropping

That means the code represents a real failure.

How the Furnace Actually Works (Why Codes Appear)

Every furnace follows a strict startup sequence:

1. Thermostat calls for heat
2. Inducer motor starts
3. Pressure switch closes
4. Ignitor heats up
5. Gas valve opens
6. Flame is detected
7. Blower starts

If any step fails:

• system shuts down
• safety lock activates
• code appears

Bryant Error Codes

Code	What It Means	What’s Happening	Most Likely Causes	What to Check
31	Pressure switch fault	Draft not proven	Blocked vent, inducer issue, hose leak	Check vent & hoses
33	Limit circuit fault	Overheating	Dirty filter, airflow restriction, blower issue	Replace filter
13	Limit lockout	Repeated overheating	Ongoing airflow issue	Fix cause + reset
14	Ignition lockout	Failed ignition	Ignitor, flame sensor, gas issue	Check ignition

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Flash Pattern	Error Code Name	Hidden Problem Inside
3 Short, 1 Long	Code 31: Pressure Switch Error	The exhaust pipe is blocked by ice or a dead bird
3 Short, 3 Long	Code 33: Limit Circuit Fault	A terribly dirty air filter trapped all the heat inside the metal box
1 Short, 3 Long	Code 13: Limit Circuit Lockout	The machine overheated too many times and locked you out completely
1 Short, 4 Long	Code 14: Ignition Lockout	The furnace not igniting because of a broken ignitor or a dirty flame sensor

Code 31 – Pressure Switch Error

What It Means

The furnace cannot confirm proper airflow through the exhaust system.

Gas will NOT be allowed to ignite.

Real Causes

• blocked intake/exhaust pipe
• ice or debris
• cracked pressure hose
• weak inducer motor
• faulty pressure switch

What to Check

• outside vent pipes
• rubber hoses
• airflow path

Code 33 – Overheating (Limit Switch)

What’s Happening

The furnace is overheating and shutting down to protect itself.

Real Causes

1. Airflow restriction (most common)

• dirty filter
• closed vents
• blocked return

2. Blower issue

• weak motor
• dirty blower wheel

3. Duct restriction

Quick Fix

• replace filter
• open vents
• restore airflow

Check the Energy.gov Furnaces page to read about deadly backdrafts.

Code 13 – Limit Lockout

What It Means

The furnace overheated multiple times and stopped trying.

This is usually the result of ignoring Code 33.

What to Do

• fix airflow problem
• reset system

Ignition Problems (Code 14)

Symptoms

• clicking sound
• no flame

Causes

• dirty flame sensor
• worn ignitor
• gas issue

Common Fix

Cleaning the flame sensor often restores operation.

Read our Furnace Wont Ignite guide to read about these fragile parts.

Real Repair Costs (2026)

Repair	DIY Cost	Pro Cost
Air Filter	$20 – $40	$100 – $150
Flame Sensor	$10 – $25	$120 – $200
Ignitor	$30 – $80	$200 – $350
Pressure Switch	$20 – $60	$150 – $300
Control Board	$150 – $300	$500 – $800

Real Diagnostic Logic (Used by Technicians)

1. Check airflow
2. Check venting
3. Verify ignition
4. Test sensors
5. Then electronics

This order prevents unnecessary repairs.

What You Can Safely Do Yourself

✔ Replace filter
✔ Clean flame sensor
✔ Check vents
✔ Inspect exhaust

What You Should NOT Do

❌ Open gas lines
❌ Replace gas valve
❌ Modify wiring

When to Call a Technician

• issue repeats
• no ignition
• multiple codes
• system short cycles

FAQ

How do I read Bryant furnace error codes correctly?

You must look through the clear plastic window on the bottom door without removing it. Count the short fast blinks first for the first number, pause, and count the slow long blinks for the second number.

What does Bryant furnace error code 31 mean?

Code 31 is a pressure switch error. It means the plastic exhaust pipe is blocked by thick snow or a dead bird, preventing the toxic smoke from escaping your house safely.

Why is my furnace flashing error code 33 over and over?

Code 33 means your machine is overheating like a hot oven. This is almost always caused by a filthy cardboard air filter trapping all the hot air inside the metal box.

What is a Bryant limit circuit lockout code 13?

Code 13 means the machine overheated too many times and the computer locked you out. You must wait three full hours for the metal parts to cool down before it will try again.

Why is my flame rollout switch open and is it dangerous?

A flame rollout switch open error is incredibly dangerous. It means the actual fire is blowing backward into your basement instead of safely up the chimney pipe.

Why does it keep shutting off?

Usually airflow or ignition problem.

Can I fix this myself?

Many basic issues – yes.

Conclusion

A blinking yellow light is not a mystery.

It is a diagnostic system designed to protect your home.

If you:

• read the flash pattern
• understand the condition
• follow the correct diagnostic order

You can solve most furnace problems quickly – without guessing or overspending.

Call our friendly team to book safe HVAC Services right now. We bring the right parts and the expensive digital testing meters.