Bryant Furnace Code 31 (Easy Fix)

If you own a Bryant furnace, you might encounter Bryant Furnace Code 31, which signals a specific issue within your heating system that requires attention.

This article explains what Code 31 means, its causes, how to diagnose it, and the steps you can take to fix it.

By understanding this error code, you can ensure your furnace operates efficiently and effectively during the colder months.

What is Bryant Furnace Code 31?

Bryant Furnace Code 31 is an error message that points to a malfunction in the pressure switch or inducer motor.

These two components are critical for ensuring proper airflow and ventilation, which are essential for your furnace to function correctly.

When this code appears, it’s a warning that your furnace is not operating as intended, and addressing the issue promptly is necessary for maintaining your home’s warmth.

Causes of Bryant Furnace Code 31

The primary causes of Bryant Furnace Code 31 revolve around airflow, pressure, and ignition issues. Here are the common culprits:

1. Clogged or Dirty Air Filter

One of the most frequent causes of Bryant Furnace Code 31 is a clogged air filter.

The air filter plays a crucial role in maintaining airflow within the furnace. When dust, dirt, or debris accumulate in the filter, it restricts airflow, which may trigger the pressure switch to activate the error code.

Solution: Regularly clean or replace your air filter according to the manufacturer’s recommendations to avoid this issue.

2. Faulty Pressure Switch

The pressure switch is responsible for ensuring proper airflow and ventilation before the furnace ignites.

If the switch malfunctions, it may fail to open or close correctly, resulting in Bryant Furnace Code 31. This issue can stem from mechanical failure, blockages, or improper calibration of the pressure switch.

Solution: Inspect the pressure switch for any visible signs of damage or wear and check if it’s opening and closing correctly. If necessary, recalibrate or replace it.

3. Vent Pipe Blockages

Vent pipes carry exhaust gases away from the furnace, ensuring that combustion air flows freely.

When these pipes become blocked—due to debris, animal nests, or ice buildup in colder weather—the airflow can be compromised. This blockage can cause the pressure switch to trigger Code 31 as a safety measure.

Solution: Regularly inspect and clear any blockages in the vent pipes to maintain proper airflow and prevent potential issues.

4. Ignition System Failure

The ignition system is a key component in starting the furnace. If parts such as the igniter, gas valve, or flame sensor fail to operate correctly, the furnace may struggle to ignite or maintain a consistent flame, leading to Bryant Furnace Code 31.

Solution: Inspect the ignition system and its components. Replace any faulty parts or seek professional assistance if the issue persists.

How to Diagnose Bryant Furnace Code 31

To address Bryant Furnace Code 31, you must first diagnose the root cause of the issue. Here’s a step-by-step guide:

Step 1: Check the Air Filter

A clogged air filter is one of the most common reasons for this error code. Inspect the filter for dirt and debris.

If it appears dirty, replace it with a new one. After replacing the filter, restart the furnace to see if the error code clears.

Step 2: Inspect the Pressure Switch

The pressure switch should open and close properly during furnace operation.

If it’s malfunctioning, it may not signal the control board correctly. Check for any visible damage or wear, and verify its operation. If it’s faulty, you may need to adjust or replace it.

Step 3: Clear Vent Pipe Blockages

Obstructions in the vent pipes can disrupt airflow, leading to pressure switch errors.

Turn off the furnace, then inspect the vent pipes for any blockages. Clear any debris or buildup with a vacuum or brush. Restart the furnace and check if the error code disappears.

Step 4: Test the Ignition System

The ignition system includes the igniter, gas valve, and flame sensor. Ensure these components are functioning properly.

If any part of the ignition system is faulty, replace the damaged components. This should resolve issues with furnace ignition and eliminate the error code.

Steps to Fix Bryant Furnace Code 31

Once you’ve diagnosed the issue, follow these steps to fix Bryant Furnace Code 31:

1. Clean or Replace the Air Filter

• Turn off the furnace and locate the air filter.
• Remove the filter and inspect it for dirt and debris.
• If necessary, replace the old filter with a new one.
• Turn the furnace back on and check if the error code clears.

2. Adjust or Replace the Pressure Switch

• Turn off the furnace and disconnect its power supply.
• Locate the pressure switch and check for proper operation.
• Adjust the settings if necessary, or replace the switch if it’s damaged or malfunctioning.

3. Clear Vent Pipe Blockages

• Turn off the furnace and inspect the vent pipes for obstructions.
• Use a vacuum or brush to remove any debris or buildup.
• Once the pipes are clear, restart the furnace and monitor if Code 31 persists.

4. Repair or Replace the Ignition System

• Disconnect the furnace power and locate the ignition system components.
• Inspect the igniter, gas valve, and flame sensor for faults.
• Replace any faulty parts or call a professional to repair the ignition system.

Preventive Maintenance Tips to Avoid Bryant Furnace Code 31

To avoid encountering Bryant Furnace Code 31 in the future, follow these preventive maintenance tips:

1. Regularly Change Air Filters

Changing the air filter every 1-3 months, depending on usage, ensures optimal airflow and prevents airflow-related issues.

2. Schedule Professional HVAC Maintenance

Arrange for an annual HVAC inspection by a certified technician. Routine maintenance can help detect and resolve potential problems before they lead to more serious issues like Code 31.

3. Ensure Proper Ventilation

Keep your vent pipes clear of debris and blockages to maintain proper airflow. Blocked vent pipes can disrupt the pressure system and trigger error codes.

Conclusion

Bryant Furnace Code 31 typically points to issues with airflow, pressure, or ignition. By diagnosing and addressing the root cause—whether it’s a dirty air filter, faulty pressure switch, vent blockage, or ignition problem—you can restore your furnace’s proper function and keep your home warm and comfortable. Regular maintenance and attention to detail will also help prevent future occurrences of Code 31, ensuring that your furnace operates efficiently for years to come.