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BRYANT DIAGNOSTIC REFERENCE STATUS LED — SHORT + LONG FLASH CODES DOC BRYANT-31

Bryant furnace code 31: Pressure Switch Did Not Close or Reopened

YOUR LIGHT: 3 SHORT + 1 LONG FLASHES — MATCH IT ABOVE

Try DIY first, then call a pro

Bryant furnaces share the Carrier control platform — this code table applies to the equivalent Bryant models. Confirm against your unit's panel label.

What does 3 short 1 long flashes mean on a Bryant furnace? If the switch stays open over 5 minutes, the inducer rests 15 minutes and retries. Official checklist: excessive wind, low inlet gas pressure (if LGPS used), disconnected or obstructed pressure tubing, defective switch.

Before you touch anything: the six signs that mean stop troubleshooting and call a pro →

Homeowner checks for Bryant furnace code 31

This is a limited outdoor observation check, not a complete furnace repair. If you smell gas or a carbon monoxide alarm sounds, leave the home right away without operating any switches, then call the gas utility or 911 from outside. Never bypass a safety switch or reset the furnace over and over.

  1. Turn the furnace off

    Turn off the furnace at the thermostat and its nearby power switch before checking the vent ends. Keep the furnace cabinet closed.

  2. Find the vent ends from ground level

    Locate the furnace intake and exhaust pipe ends where they leave the house. Only check ends you can see and reach while standing on the ground. Do not climb a ladder or go onto the roof.

  3. Clear loose snow or leaves by hand

    If it is safe to stand there, brush away loose surface snow or leaves from around the openings by hand, without tools. Do not reach into the pipes, chip at ice, or remove or modify any pipe, cap, or screen.

  4. Stop and call if anything else is wrong

    Leave the furnace off and call a technician if you find ice, a nest, a damaged pipe, or anything you cannot clear safely by hand. After clearing only loose surface snow or leaves, restore power and observe one heating cycle. If the code returns, turn the furnace off and arrange service.

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Switch and inducer testing. DIY part cost: $30–60 — a pro visit for this class of fault typically runs $150–350.

What causes it (in order of likelihood)

  1. Blocked/disconnected tubing, wind-affected venting DIY-CHECKABLE
  2. Defective pressure switch TECH

Parts referenced by this code

Pressure Switch
$30–60 · Model-specific

Always match parts against your model's parts list — part numbers vary within a series.

Questions about this code

What does 3 short 1 long flashes mean on a Bryant furnace?

If the switch stays open over 5 minutes, the inducer rests 15 minutes and retries. Official checklist: excessive wind, low inlet gas pressure (if LGPS used), disconnected or obstructed pressure tubing, defective switch.

How do I fix Bryant furnace code 31?

From ground level, check the outdoor intake and exhaust ends and clear loose snow or leaves by hand if safe. Strong wind can also play a role. Tubing, gas pressure, and switch testing need a technician.

How much does it cost to fix Bryant furnace code 31?

If a blocked vent end was the cause, clearing it may be enough. Otherwise cost depends on whether tubing, gas pressure, or the switch is responsible.

Applies to

Bryant 310/311/312 series

Different Bryant generations use different code maps. If your series isn't listed, don't assume this meaning — check your blower-door label.

Same control platform, same code: Carrier furnace code 31 · Payne furnace code 31

Verified against Carrier 58STA/58STX Installation & Service Instructions (1106202L), p.37/48

Bryant 310/311/312 series furnaces use the Carrier 58STA/58STX control platform. No separate Bryant service document is cited — confirm the code map against your unit's panel label.

Last verified 2026-07-06 · page updated 2026-10-03 · how we verify

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These codes use the same status led — short + long flash codes system.

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