Bryant Furnace Error Codes List: Every Code Explained

Every Bryant furnace error code we could verify against Bryant's own documentation — what it means, what usually causes it, and the first fix to try — in one table. Codes differ between model series, so treat your model's tech sheet as the final word.

How to read and retrieve error codes on Bryant furnaces

Every Bryant status code in these manuals is a two-digit number read off the status LED at the indicator in the blower door: the first digit is the number of SHORT flashes, the second digit the number of LONG flashes (33 = three short, three long). Three steady states frame the codes: LED continuously ON means the control has 24 VAC power; continuously OFF means check for 115 VAC at L1 and L2 and 24 VAC at SEC-1 and SEC-2; RAPID flashing means line-voltage polarity is reversed. Stored history is played back, not guessed — and the method is generation-specific. On the oldest labels (330JAV/393AAV), briefly remove and reconnect one main limit wire without removing power or the blower door; those boards erase stored codes when power is interrupted or 48 hours after each fault is cleared. The 340AAV red-LED boards and the variable-speed 355MAV erase stored codes automatically after 72 hours; the 355MAV recalls history by disconnecting the R lead (or the ABCD User Interface connector), resetting power and putting setup switch SW1-1 ON, and clears it by jumpering R, W/W1 and Y/Y2 simultaneously until code 11 flashes. The Evolution 987M changed the rule: its stored codes are NOT erased when 115- or 24-volt power is interrupted — the control stores up to the last 7 status codes in order of occurrence; with no thermostat signal present and all blower-off delays complete, set SW1-1 ON and the control flashes up to 7 codes, the 8th code always being 11, and a continuously lit amber LED afterwards confirms proper operation. On Evolution systems the Connex wall control adds its own reporting layer on top of the board: a Last 10 Events record and service screens — including Furnace Status, and, on compatible models, an Advanced Diagnostics view naming the most likely root causes of the most recent fault. The component test (setup switch SW1-6) runs the inducer, igniter and blower in sequence and reports back in codes (11, 25, 41 and 42 on the 355MAV; 11, 25, 35, 41 and 42 on the 987M). Whatever the generation, the service label printed inside your own Bryant's blower door is the chart of record for that furnace.

The complete Bryant furnace error code list

How to reset / clear error codes on Bryant furnaces

Bryant's lockouts run on documented timers, and they are not interchangeable. Limit lockout (13) and ignition lockout (14) auto-reset after 3 hours. Blower motor lockout (15, variable-speed boards) also auto-resets after 3 hours. Control circuitry lockout (45) auto-resets after 1 hour, and Bryant adds: reset power to clear the lockout — if 45 repeats, replace the control. Gas heating lockout (21) is the exception with NO auto-reset: Bryant's instruction is to turn off power and wait 5 minutes to retry. The pressure-switch behaviour under 31/32 (inducer shuts off for 15 minutes after the switch has been open 5 minutes, then retries) is a retry pause, not a lockout. Everything else on the Bryant chart is a condition code that clears when its condition clears: 33 ends when the limit or rollout switch remakes as the furnace cools (the rollout switch itself is manual-reset hardware — no timer resets it, and Bryant requires its cause to be corrected before it is reset), and 24 ends only when the 24-volt short is repaired and the fuse replaced. Interrupting power restarts a Bryant control, but on the older boards it also erases the stored fault history — read the history first, and never treat a cleared timer as a repaired furnace: an unfixed cause simply walks the control back into the same lockout.

How to diagnose any Bryant furnace code

Work the problem in this order — and stop at any point where gas, combustion or mains wiring is involved, because those belong to a licensed HVAC technician: (1) record the code exactly: count LED flashes slowly, twice, or photograph the alphanumeric display; (2) check the free things homeowners legitimately own: the thermostat is calling for heat, the furnace power switch and breaker are on, the filter is not clogged solid (a starved furnace overheats and locks out on limit codes), all vents and the return are open, and the condensate drain is not blocked on condensing models; (3) reset once — at the power switch, off for 30 seconds — then watch a full call for heat from the beginning: inducer, ignition, flame, blower, in that order; where the sequence stops is the fault family the code names; (4) a code that returns immediately is an active fault — do not keep resetting a lockout, especially any flame or limit code; (5) everything inside the burner compartment — flame sensor cleaning is the one grey area many manuals allow owners, but gas valves, burners, heat exchangers and control boards are professional work. If you smell gas at any point, leave and call the gas utility, not a helpline.

Bryant and Carrier are one code family — and Bryant's documents are still the authority for a Bryant furnace

It is true, and this page does not pretend otherwise: Bryant furnaces are built on Carrier-family control hardware, and the two-digit status-code table at the heart of this hub — short flashes for the first digit, long flashes for the second, 13 for limit lockout, 24 for the secondary fuse, 33 for the limit circuit — is the family table, which is why a Bryant service label and a Carrier service label of the same era read so much alike. This site already publishes Carrier pages on that basis. What it does not follow is that a Bryant owner should be handed Carrier's text. Bryant prints its own manuals, its own service labels and its own troubleshooting guides for Bryant models — the 355MAV troubleshooting guide, the 340AAV and 330JAV service labels, the Evolution 987M installation instructions — and every entry in this hub is written from those Bryant documents, in Bryant's wording where Bryant's wording has its own shape. The differences are not cosmetic. Bryant's variable-speed guide gives code 33 a clause the standard labels do not carry: on those models 33 also announces that the furnace has dropped into high-heat-only mode after 2 successive low-heat limit trips. Bryant's oldest label in this check (330JAV) compresses code 45 to two words — 'replace control' — where the fuller Bryant table explains the same code as a 1-hour control circuitry lockout with three named internal causes. And Bryant's generations disagree with each other in ways no borrowed chart warns you about: older Bryant boards erase their stored codes the moment power is interrupted, while the Evolution 987M pointedly does NOT — it keeps the last 7 codes through any power cut. The reporting layer is Bryant's own, too: an Evolution system reports through the Bryant Evolution Connex wall control, with its Last 10 Events record and its Furnace Status and Advanced Diagnostics service screens — not through the sibling brand's wall control and menus. Even the model badge changes what a code means in practice: 31 is a single pressure-switch code on a Legacy single-stage furnace and specifically the high-heat switch on a Preferred two-stage or Evolution variable-speed model, with 32 and 43 existing only where a second switch exists. So the working rule for a Bryant owner is the one Bryant itself prints, in effect, on every door: the service label inside YOUR furnace's blower door is the chart of record. This hub's table is Bryant's shared chart, drawn from Bryant literature across the Legacy, Preferred and Evolution lines — and where a code's meaning splits by generation, the entry says which Bryant generation it belongs to, rather than sanding the difference away. The sharpest example sits inside Bryant's own line: the oldest Bryant labels in this check retrieve stored codes by briefly removing and reconnecting a main limit wire, while the Evolution 987M manual warns, in so many words, that 'the Status Codes cannot be retrieved by disconnecting the limit switch' — on the 987M the retrieval is a setup-switch procedure, because its control and memory work differently. Two Bryant furnaces, two opposite instructions for the same job, both correct — for their own generation. The same discipline applies to hardware identity: on the variable-speed models the control learns what furnace it is running from a model plug whose number and resistance values are printed on that model's wiring diagram, and code 25 exists precisely because a plug from the wrong model (or no plug at all, after a board change) makes the control run the wrong furnace's program. None of that — the plug values, the retrieval methods, the Connex screens, the high-heat-only clause — is visible from a shared family chart; all of it is in Bryant's documents, which is why Bryant's documents are what this hub is built from.

How Bryant's short/long flash reading works — and how to read the history behind the code

A Bryant status code is two counts, not one pattern. Watch the status LED at the indicator in the blower door: it flashes a run of SHORT flashes, then a run of LONG flashes, then pauses and repeats. The short count is the first digit, the long count the second — one short and three long is 13, three short and four long is 34. Three steady states are not codes at all and are worth learning before any count confuses you: a continuously ON LED simply means the control has 24-volt power; a continuously OFF LED means check for 115 volts at L1 and L2 and 24 volts at SEC-1 and SEC-2; and RAPID flashing, with no pause structure, means line-voltage polarity is reversed (the 987M instructions add that the control will prevent heating while polarity is wrong, and that the system needs a proper earth ground for the control and flame-sensing electrode). Two of the counted codes are also not faults: 12 (blower on after power up — a 90-second blower run when the furnace is powered during a call for heat) is normal operation, and 11 (no previous code) is the history system's way of saying the cupboard is bare. Reading the ACTIVE code is only half the Bryant method, because Bryant controls remember. Stored faults are played back in order of occurrence, and the playback always terminates at 11 — on the Evolution 987M the manual spells it out: up to 7 stored codes flash, and 'the last Status Code, or 8th Code, will be code 11.' The retrieval method follows the generation. Oldest boards: briefly remove and reconnect one main limit wire, without removing power or the blower door — and note the trap in that generation, those boards erase stored codes whenever power (115V or 24V) is interrupted, and in any case 48 hours after each fault clears, so a well-meaning power cycle before reading the history destroys the evidence. The 340AAV red-LED boards and the variable-speed generation keep codes for 72 hours, still erasing on power interruption on the red-LED boards; the 355MAV plays its history back through setup switch SW1-1 (with the R lead or ABCD User Interface connector disconnected) and can be deliberately cleared by jumpering R, W/W1 and Y/Y2 until 11 flashes. The Evolution 987M breaks the family pattern on purpose: stored codes are NOT erased when power is interrupted, all 7 survive, and playback is SW1-1 ON with no thermostat signal present and every blower-off delay completed. On top of the board, an Evolution Connex wall control keeps its own Last 10 Events record and service screens, so an Evolution owner may meet the same fault twice — once as flashes at the furnace, once as an event at the wall. Read in this order: active code first, stored history second, door chart always — and only then reset anything. One more Bryant voice belongs in the reading discipline: the component test. It is not a code and not a history, but a controlled experiment the control runs on itself — on demand it exercises the inducer, the hot-surface igniter and the blower in sequence, then reports the outcome in the same flash language (the 355MAV reports 11, 25, 41 or 42 after the test; the 987M's list is 11, 25, 35, 41 or 42). A post-test 11 says the blower motor tested OK; a 41 or 42 at the end of a component test condemns the blower or inducer without a single heating cycle having run. Owners should know the test exists — technicians reach for it constantly on Bryant ignition and motor complaints — and should also know its limits: the post-test codes are only as meaningful as the Bryant table that defines them, and one of them (35) appears in no Bryant status-code table this site could verify, which is why it sits in this hub's unverified list rather than wearing an invented meaning. That restraint is the whole method in miniature: read what Bryant printed, in the order Bryant printed it, and let an undefined code stay undefined until Bryant defines it.

Blink codes, display codes and lockouts

Two generations of fault reporting live side by side on modern furnaces. Older and simpler boards report through a single LED: a repeating count of flashes, read slowly against the chart printed inside the blower door — that chart, for your exact model, outranks any list on the internet, including this one. Newer communicating furnaces show alphanumeric codes (the E-series in the table above) and store a fault history a technician can scroll. Both generations share the lockout idea: after a set number of failed attempts at the same step — ignition is the classic — the board stops trying for a period (often an hour, or until power is cycled) instead of cycling forever against a fault that could overheat or flood the burners with unburned gas. A furnace in lockout is not broken by the lockout itself; it is a furnace that has already failed the same step repeatedly and is waiting for someone to find out why.

Furnace codes are also seasonal in a way washer codes are not. The first cold snap produces a wave of ignition and flame codes from furnaces that sat idle all summer — oxidised flame sensors, spider-nested burners, pressure-switch hoses holding condensate from the cooling season. Deep-winter adds frozen condensate lines on high-efficiency models and intake/exhaust terminations blocked by snow or ice, which present as pressure-switch codes. A code that appears once, on the coldest night of the year, and never again has often met its cause already; a code that appears every cycle, in any weather, is a component asking to be tested.

The most searched Bryant furnace codes, in detail

13 — Limit circuit lockout

Code 13 is code 33 that did not clear in time — Bryant prints the relationship on every service label ('Refer to status code #33') because 13 has no separate cause list: it is the lockout the limit circuit escalates to. Two documented paths lead here. The clock path: a limit or rollout switch opens (33) and is still open 3 minutes later — the heat is not being carried away, or the switch cannot remake. The count path, worded in the 355MAV guide and the 577D section: 10 successive limit trips during high-heat also produce the lockout, even if each trip remade quickly — the control has counted a furnace that overheats as a pattern, not an accident. Once in 13, gas heating stops: Bryant's documented behaviour is an auto-reset after 3 hours, after which the furnace may try again — and lock out again if the switch is still open or the trips resume. The rollout branch hides inside 13: the flame rollout switch is a manual-reset device, so once tripped it is open forever until a human resets it — a rollout event sails through the 3-minute mark and presents as a 13 lockout with no hot furnace left to feel. The 330JAV label says it in one line under 13: 'Reset switch or replace fuse link.' A 13 on a cold furnace is therefore often a rollout (or a failed switch or connection), while a 13 arriving mid-evening after repeated short heat runs is the airflow story at its end stage. Either way, the 3-hour auto-reset is a safety pause, not a repair — a furnace spending its winter cycling between 33, 13 and a 3-hour wait is being damaged by the pattern, trip by trip.

Most likely cause: The code 33 airflow family, persisted — Everything on Bryant's 33 list that lasts longer than 3 minutes or repeats 10 times in high-heat: dirty filter or restricted duct system first, then the blower family. A marginal restriction producing forgiving 2-minute trips in October produces 13s in January, when runs are longest.

First check: SAFETY: a 13 is a safety lockout on a gas appliance. Never bypass the limit circuit, and never reset a rollout switch before its cause is corrected — Bryant's caution is explicit. Gas smell, soot or scorching at the burner compartment, or a CO alarm: furnace off, licensed technician (gas utility for a gas smell).

If it keeps coming back: A 13 that returns after its 3-hour auto-reset is a furnace reporting that nothing changed while it waited — because nothing did. Recurring 13s concentrate on the coldest nights (longest runs, weakest airflow), each cycle another set of overheating trips on the heat exchanger. A 13 appearing on mild days after a winter of cold-day 13s is the restriction or blower worsening on schedule; treat the pattern as a deadline, not a personality trait.

24 — Secondary voltage fuse is open

Code 24 is the Bryant control protecting itself, and it starts with what 'secondary voltage' means: the transformer steps line voltage down to the 24 VAC that runs everything the furnace thinks with — thermostat circuit, limit circuit, pressure switches, gas valve, and accessories such as the humidifier terminal. When a wire in that 24-volt web shorts to ground or common, the fuse on the control opens before the short can take the transformer or board with it. The furnace then presents confusingly: the thermostat may be blank (its power came through the same circuit), yet the control still flashes 24 at the blower-door indicator — alive on its line-voltage side, reporting its low-voltage side down. Bryant's 355MAV troubleshooting for 24 is built on one lesson: do not hunt the short — isolate it. The technician disconnects the User Interface (ABCD) connector or all thermostat leads (including anything on the HUM terminal), fits a new fuse, restores power, then re-energises the circuits one call at a time — heat, high-heat, cooling — watching which stage makes 24 return. Each branch has a named suspect: the limit circuit's red wires to chassis ground convict the limit circuit; the pressure-switch wires convict their circuits in turn; the gas valve's blue wire to ground convicts its wiring or the valve; a 24 arriving only in cooling convicts the outdoor-unit wiring or contactor; a 24 arriving at blower start sends the flow to the humidifier's draw — and finally to Bryant's most experience-soaked note in the guide: loose or torn insulation shorting intermittently against the limit switches. The fuse is the messenger and the sacrifice; the short is the fault.

Most likely cause: Short in the thermostat wiring — The cause Bryant's labels name outright: a short in the secondary-voltage wiring 'including thermostat leads' (the 393AAV label adds 'shorting to ductwork or furnace cabinet'). Thermostat cable is thin, stapled, and run through walls and duct chases — chafed insulation, a screw or staple through the bundle, or a bare conductor on sheet metal is the classic 24.

First check: SAFETY: low voltage is not no voltage — the same cabinet holds 115V (and the gas train). Power OFF at the furnace switch before opening panels or touching the fuse, every time. Gas and board work are licensed-technician territory; the checks below are observation and isolation logic, not an invitation to rewire circuits.

If it keeps coming back: Intermittent 24s are the ones that come back: Bryant's flow ends by warning that loose or torn insulation can short intermittently against the limit switches when vibration or temperature moves it — and that a failing outdoor contactor can draw excessively only sometimes. A 24 returning weeks later, in a different mode, usually means the short neighboured the repaired one (same cable run, same chafe point). Describe the mode and stage pattern precisely when you call; on this code, the pattern is the diagnosis.

33 — Limit circuit fault

Code 33 is Bryant's overheating-and-rollout report, with identical wording across the whole Bryant line — limit or flame rollout switch open, blower runs 4 minutes or until the switch remakes, 3 minutes to lockout 13 — printed on the single-stage 340AAV, 330JAV and 393AAV service labels, in the 577D control section, and in the variable-speed 355MAV guide. The limit circuit is a series string of safety switches watching the heat exchanger and the burner compartment. The main limit opens when the air around the exchanger gets too hot — which on a gas furnace almost always means heat is being made faster than air carries it away. The flame rollout switch watches the burner box instead: it opens when flame or hot gas escapes where it should never be, and unlike the main limit it does not remake on its own — it is a manual-reset device, and Bryant's 355MAV caution is blunt about the order of operations: correct inadequate combustion-air supply or component failure BEFORE resetting the switch. The control's behaviour while 33 shows is deliberate cooling, not confusion: burners off, blower running a full 4 minutes (or until remake, whichever is longer) to pull stored heat out of the exchanger. The variable-speed generation adds one clause the older labels do not print: on the 355MAV, 33 also reports the furnace operating in high-heat-only mode after 2 successive low-heat limit trips. Bryant's own proof test shows the code doing its designed job: gradually block the return air on a running furnace, and the moment the limit shuts the burners off, a 33 appears.

Most likely cause: Dirty filter or restricted duct system — First on Bryant's check list for 33 on every label. A loaded filter, closed or blocked registers and returns, or an undersized or crushed duct run starves the heat exchanger of airflow, and the limit opens to protect it.

First check: SAFETY: this is a gas appliance reporting overheating or flame rollout. Never bypass a limit or rollout switch to get heat, and never reset a tripped rollout switch until the cause is found — Bryant's caution requires correcting inadequate combustion-air supply or component failure first. Gas smell, scorch marks or soot at the burner compartment, or a CO alarm: furnace off, licensed technician (gas utility for a gas smell).

If it keeps coming back: A 33 that returns after a filter change and open registers means the restriction is deeper or the blower is fading: a matted blower wheel, a clogged indoor coil, collapsing duct liner, or a capacitor losing strength week by week. A returning rollout trip is more serious — venting or combustion air is still wrong — and must not be managed by repeated manual resets. Each limit trip is a thermal cycle the exchanger did not need; a furnace tripping weekly is ageing its exchanger on every trip.

Less common and model-specific codes

Search data shows owners also meet these codes on Bryant furnaces: 35, 44. They are not part of the core code list Bryant publishes for most models — several are series-specific, abbreviated display readings, or codes carried over from a sister platform — so we do not publish meanings for them rather than guess. Treat them by symptom: note what the machine was doing when the code appeared (filling, draining, heating, spinning), run one full power cycle (5 minutes off), and if the code returns, match the symptom to the closest documented family in the table above and check the tech sheet stored inside your machine for the model-specific definition.

Deep-dive guides for the most searched codes

Related guides

Facts on this page were checked against manufacturer documentation: shoredist.com · manuzoid.com · www.manualshelf.com · www.manualsdir.com · www.manualshelf.com · manualsdump.com · manualsdump.com · www.manualsdir.com · www.manualslib.com · manuals.plus