HVAC Code Lookup

Bryant Furnace: 3 Flashes

A Bryant furnace LED pattern starting with 3 flashes matches 11 documented codes: 31.2, 31.3, 31.6, 31.7, 32.1, 32.2, 33.1, 33.2, 34.1, 34.2, 34.3. Watch the full pattern (short vs. long flashes) to tell them apart — all 11 are explained below.

Code 31.2: Open secondary pressure switch

WarningShown as: 3 short flashes, 1 long flash; 31.2 on the display

Open secondary pressure switch (HPS) - the high-heat pressure switch did not close, or reopened, when the control needed it.

Manual wording: “31 2 Open secondary pressure switch (HPS)”

Documented for: 912SE

Likely causes, most common first

  1. Restricted vent or blocked intake/exhaust termination
  2. Plugged condensate drain
  3. Excessive wind at the vent
  4. Disconnected or obstructed pressure tubing
  5. Defective inducer motor or low inducer voltage
  6. Defective pressure switch

What you can safely check yourself

  • Go outside and check the furnace intake and exhaust pipes for snow, ice, leaves, or a nest and clear any blockage
  • Check the condensate drain line and trap for a clog
  • Replace a dirty air filter

When to call a technician

If the vents are clear and the drain is open, the inducer, pressure switch, or tubing needs a technician. Never jumper a pressure switch.

A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Source

Full page for Bryant code 31.2

Code 31.3: Secondary pressure switch lockout - the secondary

Soft lockoutShown as: Major code 31 on the LED (3 short, 1 long); 31.3 on the display

Secondary pressure switch lockout - the secondary (high-heat) pressure switch failed to close after three trials.

Manual wording: “31 3 Secondary PS Lockout - failed to close secondary PS after three trials”

Documented for: 912SE

Likely causes, most common first

  1. Restricted or improperly sized vent
  2. Plugged condensate drain
  3. Obstructed or disconnected pressure tubing
  4. Failed inducer motor or pressure switch

What you can safely check yourself

  • Check outdoor vent terminations for snow, ice or debris
  • Check the condensate drain and trap for a clog

When to call a technician

Three failed attempts to make the pressure switch means the venting or the inducer needs a technician's inspection.

A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Source

Full page for Bryant code 31.3

Code 31.6: Open secondary pressure switch - the high-heat pressure switch did not close for one minute after the gas valve closed, or it has reopened

WarningShown as: Major code 31 on the LED (3 short, 1 long); 31.6 on the display

Open secondary pressure switch - the high-heat pressure switch did not close for one minute after the gas valve closed, or it has reopened.

Manual wording: “31.6 OPEN SECONDARY PRESSURE SWITCH - HPS did not close for one minute after gas valve closed or has reopened.”

Documented for: 926TC

Likely causes, most common first

  1. Failed to close secondary pressure switch after three trials
  2. Excessive wind
  3. Restricted vent
  4. Defective inducer motor
  5. Low inlet gas pressure (if LGPS used)
  6. Inadequate combustion air supply
  7. Improper vent sizing
  8. Disconnected or obstructed pressure tubing
  9. Condensate drainage restricted or blocked

What you can safely check yourself

  • Check the outdoor intake and exhaust pipes for blockage from snow, ice, leaves, or nests
  • Check the condensate drain line and trap for a clog

When to call a technician

Vent sizing, inducer performance, and pressure switch calibration are technician diagnostics.

A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Source

Full page for Bryant code 31.6

Code 31.7: High heat only for the next cycle - the high-heat pressure switch failed to close within 75 seconds while transitioning from low to high heat

WarningShown as: Major code 31 on the LED (3 short, 1 long); 31.7 on the display

High heat only for the next cycle - the high-heat pressure switch failed to close within 75 seconds while transitioning from low to high heat.

Manual wording: “31.7 HIGH HEAT ONLY for next cycle- HPS failed to close in 75s when transitioning from low to high heat.”

Documented for: 926TC

Likely causes, most common first

  1. Same venting and pressure switch causes as code 31.6

What you can safely check yourself

  • Check outdoor vent terminations for blockage
  • Check the condensate drain for a clog

When to call a technician

If the furnace keeps forcing itself to high heat, have a technician check the high-heat pressure switch and venting.

A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Source

Full page for Bryant code 31.7

Code 32.1: Open main pressure switch

WarningShown as: 3 short flashes, 2 long flashes

Open main pressure switch (LPS) - the main low-heat pressure switch is open when it should be closed.

Manual wording: “32 1 Open Main pressure switch (LPS)”

Documented for: 912SE

Likely causes, most common first

  1. Restricted vent or blocked intake/exhaust termination
  2. Plugged condensate drain
  3. Disconnected or obstructed pressure tubing
  4. Defective inducer motor
  5. Defective pressure switch
  6. Excessive wind

What you can safely check yourself

  • Check outdoor intake and exhaust pipes for snow, ice, leaves, or a nest
  • Check the condensate drain line and trap for a clog
  • Replace a dirty filter

When to call a technician

If venting and drain are clear, the inducer or pressure switch needs testing by a technician.

A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Source

Full page for Bryant code 32.1

Code 32.2: Open main pressure switch

WarningShown as: Major code 32 on the LED (3 short, 2 long); 32.2 on the display

Open main pressure switch. If the low-heat pressure switch stays open longer than 5 minutes or reopens, the inducer shuts off for 15 minutes before retrying. On a two-stage furnace this can force the next cycle to high heat only.

Manual wording: “32.2 OPEN MAIN PRESSURE SWITCH - If LPS is open longer than 5 minutes or has reopened, inducer shuts off for 15 minutes before retry.”

Documented for: 926TC

Likely causes, most common first

  1. Restricted or improperly sized vent
  2. Plugged condensate drain
  3. Obstructed pressure tubing
  4. Defective inducer motor or pressure switch
  5. Excessive wind

What you can safely check yourself

  • Check outdoor vent terminations for snow, ice, or debris
  • Check the condensate drain and trap for a clog
  • Replace a dirty air filter

When to call a technician

Have a technician confirm vent sizing and pressure switch operation. Do not bypass the switch.

A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Source

Full page for Bryant code 32.2

Code 33.1: A switch has opened in the main limit circuit - the limit or flame rollout switch is open

Soft lockoutShown as: 3 short flashes, 3 long flashes

A switch has opened in the main limit circuit - the limit or flame rollout switch is open. The blower runs 4 minutes or until the switch remakes. If the switch stays open longer than 3 minutes the code becomes lockout 13.

Manual wording: “33.1 A SWITCH HAS OPENED IN THE MAIN LIMIT - Indicates the limit or flame rollout is open. Blower will run for 4 minutes or until open switch remakes whichever is longer.”

Documented for: 926TC, 912SE

Likely causes, most common first

  1. Dirty filter or restricted duct system
  2. Loose blower wheel
  3. Defective switch or connections
  4. Defective blower motor
  5. Improper gas input adjustment

What you can safely check yourself

  • Check and replace the air filter - a clogged filter is by far the most common cause
  • Make sure supply registers and return air grilles are open and unblocked
  • Make sure the furnace door is fully seated

When to call a technician

If the code returns after a filter change, the limit or rollout switch is tripping for a reason a technician must find. The flame rollout switch requires manual reset and must never be reset without diagnosing why it tripped.

A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Sources

Full page for Bryant code 33.1

Code 33.2: Lockout to high heat only for the current cycle, following limit circuit trips

WarningShown as: Major code 33 on the LED (3 short, 3 long); 33.2 on the display

Lockout to high heat only for the current cycle, following limit circuit trips.

Manual wording: “33.2 LOCKOUT - High Heat Only for current cycle.”

Documented for: 926TC

Likely causes, most common first

  1. Dirty filter or restricted duct system
  2. Loose blower wheel
  3. Defective switch or connections
  4. Defective blower motor
  5. Improper gas input adjustment

What you can safely check yourself

  • Replace the air filter
  • Open any closed supply registers and clear blocked return grilles

When to call a technician

Repeated limit trips need a technician to check airflow, blower performance, and gas input rate.

A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Source

Full page for Bryant code 33.2

Code 34.1: Ignition fault during four consecutive ignition trials - the furnace tried to light four times without proving flame

WarningShown as: 3 short flashes, 4 long flashes

Ignition fault during four consecutive ignition trials - the furnace tried to light four times without proving flame.

Manual wording: “34.1 IGNITION FAULT - during four consecutive ignition trials.”

Documented for: 926TC, 912SE

Likely causes, most common first

  1. Gas valve turned off or manual shut-off valve closed
  2. Green/yellow ground wire not connected to the furnace sheet metal
  3. Flame sensor grounded or dirty
  4. Defective hot surface igniter
  5. Low inlet gas pressure

What you can safely check yourself

  • Check that other gas appliances still work, confirming gas service is on
  • Make sure the furnace door is fully closed and latched

When to call a technician

Checking the igniter, flame sense current, and gas valve requires opening a live gas appliance. Call a technician instead of attempting it.

A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Sources

Full page for Bryant code 34.1

Code 34.2: After successful ignition

Safety faultShown as: Major code 34 on the LED (3 short, 4 long); 34.2 on the display

After successful ignition (flame proven), flame was lost before the heating blower on-delay finished.

Manual wording: “34.2 AFTER SUCESSFUL IGNITION flame loss before heating blower on delay”

Documented for: 926TC, 912SE

Likely causes, most common first

  1. Oxide buildup on the flame sensor
  2. Low inlet gas pressure
  3. Poor control ground continuity
  4. Inadequate flame carryover or rough ignition

What you can safely check yourself

  • Confirm other gas appliances in the house are working normally

When to call a technician

Flame loss right after ignition is a combustion and flame-sensing problem for a technician; do not attempt to clean or reposition the flame sensor yourself.

A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Sources

Full page for Bryant code 34.2

Code 34.3: After successful ignition

Safety faultShown as: Major code 34 on the LED (3 short, 4 long); 34.3 on the display

After successful ignition (flame proven), flame was lost after the heating blower on-delay.

Manual wording: “34.3 AFTER SUCCESSFUL IGNITION flame loss after heating blower on delay”

Documented for: 926TC, 912SE

Likely causes, most common first

  1. Oxide buildup on the flame sensor
  2. Low inlet gas pressure
  3. Poor control ground continuity
  4. Airflow disturbing the flame

What you can safely check yourself

  • Check that the air filter is clean and supply/return vents are open

When to call a technician

Losing flame once the blower comes on often points at gas pressure or flame sensing. Have a technician measure flame current and manifold pressure.

A Bryant furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Sources

Full page for Bryant code 34.3

Other Bryant codes