Trane & American Standard Part Number Decoder

What the three-letter prefixes mean, why CNT5482 and CNT05482 are the same part, and how to find your number when it is nowhere on the part.

Open To Public HVAC Parts · Dallas, TX · Updated August 2026

READ THIS BEFORE YOU CALL

This chart is a free reference tool, here for you to use on your own. Open To Public HVAC Parts is a walk-in parts counter in Dallas, Texas.

  • In-store sales only — no shipping, no online orders.
  • We cannot look up or cross parts over the phone or by email.

If you are local, bring the old part and your unit model number to 10226 Plano Rd, Suite 104, Dallas TX and we will work through it with you at the counter.

Trane and American Standard service parts are numbered three letters plus five digitsCNT05482, BLW00889, FAN04073. The letters tell you what kind of part it is. The digits are just a serial. And the single most common reason people cannot find their part is the zeros.

The zero rule — read this first

CNT5482 and CNT05482 are the same part. So are BLW0889 and BLW00889, KIT3033 and KIT03033, FAN4073 and FAN04073, IGN0145 and IGN00145.

Trane’s official format is always five digits after the prefix. But Trane stamps the short version on the part itself, and that is what ends up on invoices, in parts lists and in your search bar. If your part shows four digits, put a zero in front. If it shows three, put two zeros in front.

There is no ambiguity in doing this. Every number is exactly five digits, so a four-digit number can only pad back one way. CNT5482 cannot mean anything except CNT05482.

Finding your number when the part does not have one

  1. Look for three letters and digits — that is the orderable number. If you have it, you are done.
  2. No luck? Look for a “D” number like D341213P01. That is Trane’s engineering number and it is very often the only Trane marking physically on the part.
  3. Look for the actual manufacturer’s number — White-Rodgers, Fasco, Genteq and US Motors build most of these, and their own number is usually printed right on it.
  4. Failing all of that, get the unit model number off the data plate and work forward from the equipment.

What the three letters mean

The prefix is the part category. These are the ones we can verify against Trane’s own catalog descriptions — we have deliberately left out prefixes we could not confirm rather than guess at them.

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PrefixMeansWhat it actually is
CNTControlFurnace controls, defrost controls, ignition controls. Not strictly boards — see the warning below.
BRDBoardPCB assemblies. This is the true “board” prefix.
CTRContactorContactors.
BLWBlowerInducer, draft and combustion blower assemblies.
MOTMotorBlower motors, condenser fan motors, ECM motor and module sets.
FANFanFan BLADES — the propeller, not the motor.
WHLWheelBlower wheels and squirrel cages.
IGNIgnitorHot surface ignitors and spark electrodes.
KITKitMulti-piece service kits — ignitor kits, inducer kits, LP conversion kits.
SENSensorFlame sensors, coil and defrost sensors, thermistors.
SWTSwitchPressure switches, door interlocks, limit switches.
THTThermostat / thermalLimit thermostats, thermal cutouts, terminator switches.
VALValveGas valves, expansion valves, EEVs, reversing valves.
CPTCapacitorRun and start capacitors.
RLYRelayRelays, time delay relays, start relays.
TRRTransformerControl transformers.
MODModuleIgnition modules, motor control modules, ReliaTel modules.
COMCompressorCompressors.
BNRBurnerInshot burners.
HTRHeaterCrankcase heaters, electric heaters.
DHYDehydratorLiquid line filter-driers.
FUSFuseFuses and fusible links.
GKTGasketGaskets.
WIRWireWiring harnesses.
PANPanDrain pans.
CHGChargerField charger assemblies.
Two prefixes that trip people up.
FAN is a fan blade, not a fan motor. FAN04073 is a 28-inch aluminium propeller. The condenser fan motor would be a MOT number. This is the easiest wrong part to order on the whole list.
CNT means “Control,” not “control board.” It is a board about nine times out of ten, but the CNT range also contains gas valves and ignition controls. If you specifically want a board, BRD is the prefix that always means one.

There are another seventeen prefixes that definitely exist in Trane’s catalog — ADP, BKR, COL, COR, ELC, ELM, HLD, INS, LAT, ORF, PMP, PNL, RCK, RSR, SHE, TER, TUB — but we could not find a source stating what they stand for, so we are not going to invent expansions for them. Note also that XFR, DFR, FLT, HEA, SEC and PRD are not Trane prefixes, even though they look like they should be. Transformers are TRR, defrost controls are CNT, filter-driers are DHY.

Why one part has four different numbers

This is the thing that makes Trane parts genuinely harder to source than most brands, and almost nobody explains it. A single Trane part can carry four numbers, and only one of them can be ordered.

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NumberExampleWhere you find itCan you order it?
Service part numberCNT06585Trane catalog, parts lists, invoicesYes. This is the one.
Trane engineering numberD343687P02Printed on the partNo — cross-reference only
OEM manufacturer number50V54-571-01Printed on the part by whoever actually built itNo — but it is how you find the aftermarket equivalent
“X” numberX13690250550On some boards and inducersNo — cross-reference only

The practical consequence

The CNT or BLW or MOT number is frequently not printed on the physical part at all. White-Rodgers, Fasco, Genteq and US Motors build these parts for Trane, and the part carries their number plus a D-number. The Trane service number lives in the catalog, not on the brass.

So if you have pulled a board out of a Trane furnace and there is no CNT number anywhere on it, nothing is wrong. Work from the D-number or the manufacturer’s number instead — or bring the part and the model number to the counter.

It also means aftermarket cross-references are usually published against the D-number, not the CNT number. If searching CNT05165 gets you nowhere, search D341213P01.

Trane and Ameristar parts we stock20 numbers

Both spellings of every number, because you will see it written either way. OEM means the genuine Trane part; aftermarket direct means a different manufacturer’s part that is a direct functional replacement.

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Trane numberShort formWhat it isWhat we carry
CNT09646CNT9646Integrated furnace control board, S8X1 seriesOEM Trane
CNT09648CNT9648Integrated furnace control board, A801X (RunTru)OEM Trane
CNT07737CNT7737Integrated furnace control, constant torque (X13) furnacesOEM Trane
CNT05482CNT5482Heat pump defrost control boardOEM Trane
CNT05001CNT5001Universal heat pump defrost control, 24VACOEM Trane
CNT05165CNT5165Integrated furnace control, 80V hot surface ignitorAftermarket direct — White-Rodgers 50A65-5165
CNT03797CNT3797Integrated furnace control, 120V hot surface ignitorAftermarket direct — White-Rodgers 50A55-3797
BRD05765BRD5765Main control board PCB — Ameristar air handlerAftermarket
RLY02807RLY2807Fan control board / time delay relayWhite-Rodgers 57T01-843
BLW00889BLW0889Inducer motor assembly, 1-stage, 1/50 HP, 115VAftermarket direct — FB-RFB337
IGN00145IGN0145Hot surface ignitor, nitride, 80VWhite-Rodgers 768A-815
IGN00152IGN0152Hot surface ignitor, nitride, 120VAftermarket direct — Supco SSN087KS
KIT03033KIT3033Ignitor kit, hot surfaceAftermarket direct — Supco SKIT03033
SEN01114SEN1114Flame sensorTrane
FAN04073FAN4073Fan blade — 3 blade, 28″, 18° pitch, CCW, hub on intakeIn stock
FAN06720FAN6720Fan blade — 3 blade, 23″, CCW, hub on intakeIn stock
VAL09030VAL9030Furnace gas valve, 2-stage, fast open, 1/2″In stock — supersedes VAL06376 and VAL08027
SWT01714SWT1714Door interlock switch — also fits Carrier and YorkIn stock
SWT02173SWT2173Manual limit switch, tear drop, L310°In stock
SWT04232SWT4232Dual pressure switch, −0.17″ / −0.50″In stock
Commonly searched, and we do not stock them: MOT13129 (ECM X13 blower motor, 1 HP — Trane engineering number D672365P11, crosses to US Motors W51-11BDV-04), MOT09231 / MOT9231 (ECM variable speed motor and module set, D341314P03), and CNT08120 / CNT8120 (2-stage integrated furnace control, D344782P03). We would rather tell you that here than have you drive out.

Supersessions — old numbers rolled into new ones

Trane supersedes aggressively, and it goes one direction: one new number absorbs several old ones. Always look your number up as a “replaced by” rather than assuming the old one is still made.

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Old numbersReplaced byPart
CNT03076 · CNT03798 · CNT05164CNT05165Integrated furnace control, 80V HSI
CNT07639 · CNT07872CNT09646Integrated furnace control, S8X1
CNT07940CNT09648Integrated furnace control, A801X
CNT04711CNT07737Integrated furnace control, constant torque
CNT02789 · CNT02891 · CNT03799CNT03797Integrated furnace control, 120V HSI
VAL06376VAL08027VAL09030Furnace gas valve, 2-stage
BLW00473 · BLW00522 · BLW01312 · BLW01437BLW00889Inducer assembly
IGN00051 · IGN00052 · IGN00053 · KIT02863KIT02865KIT03033Ignitor kit
IGN00104 · IGN00117IGN00145Hot surface ignitor, 80V
IGN00146IGN00152Hot surface ignitor, 120V
FAN03127 · FAN04003FAN06720Fan blade, 23″
BRD04300BRD05765Main control board PCB
CTR00205 · CTR00208 · CTR00248 · CTR00260 and moreCTR02573Contactor, 2-pole 30A — one part replacing a dozen
Obsolete without a successor is a real situation with Trane. A large share of the older CNT range is discontinued with nothing offered in its place — CNT05165 and CNT03797 among them, and at least one dealer reports BRD05765 is no longer available even from Trane. That is exactly why we stock the White-Rodgers 50A65-5165 and 50A55-3797. When the OEM board is gone, the aftermarket direct is not a downgrade — it is the only fix.

Aftermarket equivalents

These are published crosses, not guesses. In most cases the aftermarket manufacturer is the company that built the Trane part in the first place, which is why the crosses are reliable.

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Aftermarket partMakerCrosses to TranePart type
50A65-5165White-Rodgers / CopelandCNT05164, CNT05165Integrated furnace control, 80V HSI
50A55-3797White-RodgersCNT02789, CNT02891, CNT03799Integrated furnace control, 120V HSI
50H47-475-02White-RodgersCNT09647Integrated furnace control PCB
57T01-843White-RodgersRLY02807 / CNT05981Time delay relay / fan control
36J54-214White-RodgersVAL06376, VAL08027, VAL09030Furnace gas valve
768A-815White-RodgersIGN00145Hot surface ignitor, 80V
SSN0145SupcoIGN00145Hot surface ignitor, 80V
SSN087KSSupcoIGN00152Hot surface ignitor, 120V
SKIT3033SupcoKIT03033Ignitor kit
W51-11BDV-04US Motors / GenteqMOT13129 (D672365P11)ECM X13 blower motor, 1 HP
A369FascoBLW00521Inducer assembly
70218928FascoBLW00451Combustion blower
66311PackardBLW01311 (D965130P01)Inducer assembly
ICM2812-KIT, ICM2913ICM ControlsVarious — ICM keeps a dedicated Trane board categoryFurnace control boards

The pattern worth knowing: aftermarket crosses for Trane are almost always published against the D-number rather than the CNT or BLW number, because White-Rodgers, Fasco and Genteq know the part by the engineering number they built it to. A cross search that fails on the service number will often succeed on the D-number.

Genuinely universal categories, where aftermarket wins on price and availability: capacitors, contactors, relays, transformers, ignitors, flame sensors, door switches, fuses and gaskets. The SWT01714 door switch literally crosses to Carrier and York. Largely closed categories where you are mostly buying Trane: boards, inducer assemblies, ECM motor and module sets, fan blades, gas valves and coils.

Trane, American Standard, Ameristar and RunTru

Four badges, one company, one parts catalog. This confuses people constantly, so here is the map:

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BadgeTierModel prefixesParts
TranePremium4TTR / 4TTV / 4TTL (AC), 4TWR / 4TWV (heat pump), S8X1 / S9X1 / S9V2 (furnace), TAM / TEM (air handler). Older: 2TTR, TUD, TDD, TUHThe base catalog
American StandardPremium — same equipment, different badge4A7A / 4A7V (AC), 4A6V / 4A6H (heat pump), S8X / S9X (furnace). Older: AUD, ADD, AUHIdentical part numbers. There is no separate American Standard service numbering.
RunTru by TraneValueA801X, A951X and similarSame prefix system. CNT09648 is the A801X board.
Ameristar by American StandardValueM4AC4 (AC), M4HP4 (heat pump), M4AH4 (air handler), M801P (furnace), M4CX (coil)Same prefix system, routed through Trane Supply. BRD05765 is an Ameristar board.

On Ameristar parts specifically

Ameristar furnace parts and control boards use the same three-letter Trane numbering and come through the same catalog. Generic components — contactors, capacitors, ignitors, flame sensors, blower motors — interchange with Trane by specification.

But do not assume a Trane part fits an Ameristar unit just because the brands are related. The value brands use cost-reduced boards and blowers carrying their own numbers, and there is no published Trane-to-Ameristar cross-reference table. Match on the part number and the physical specification, not on the badge.

Trane’s marketing tiers are XR (base), XL (mid), XV (variable speed) and XC (top). American Standard calls the same boxes Silver, Gold and Platinum. “Service First” is Trane’s own OEM parts brand — if a customer says Service First, they mean genuine Trane.

Reading the unit model number

When the part number is gone, the model number gets you there. Trane’s outdoor unit numbering is one of the more readable in the industry:

4 T W R 6 036 A 1 0 0 0 B

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PositionMeaningValues
1Refrigerant4 = R-410A · 2 = R-22 (older equipment)
2BrandT = Trane · A = American Standard
3Product typeT = split air conditioner · W = split heat pump · X = coil
4FamilyR = XR · L = XL · V or Z = XV
5SEER6 = 16 SEER, and so on
6–8Nominal capacityBTU divided by 1000. 018 = 1.5 ton, 024 = 2, 030 = 2.5, 036 = 3, 042 = 3.5, 048 = 4, 060 = 5
9–14Connections, revision, parts identifierNot needed for most lookups
The 10-second version: find the three-digit group right after the series letters and divide by 12. 4TTR6036 is a 3 ton. 2TTR2024 is a 2 ton R-22 unit. Furnaces read differently — S8X1C100M5 is 100,000 BTU input, and in S8X1 the 8 is the AFUE (80%), X is multi-position and 1 is single stage.

The data plate lives on the top right of the back of an outdoor unit, on a side panel on a furnace, on the front panel of an air handler or coil, and on the rear door of a packaged unit.

Questions we get at the counter

Is CNT5482 the same as CNT05482?

Yes. Trane numbers are always five digits after the prefix, so a four-digit version is just the same number with the leading zero dropped. Trane prints the short form on the part itself, which is why both are everywhere. The same goes for BLW0889 and BLW00889, FAN4073 and FAN04073, KIT3033 and KIT03033.

There is no Trane number anywhere on my part. Did somebody replace it already?

Probably not. The CNT, BLW or MOT number often is not printed on the part at all — it lives in Trane’s catalog. What is on the part is a D-number like D341213P01 and whatever number the actual manufacturer put there, usually White-Rodgers, Fasco or Genteq. Work from either of those, or from the unit model number.

Is a Trane part the same as an American Standard part?

Yes, identically. Same company, same equipment, same service part numbers. Only the model numbers on the outside of the box differ — Trane uses a T in the model prefix and American Standard uses an A.

Do Ameristar parts have their own numbers?

No, Ameristar uses the same three-letter Trane numbering and comes through the same catalog. That said, the value brands use some cost-reduced boards and blowers with their own part numbers, so match on the number rather than assuming a Trane part fits.

My board is discontinued and Trane has no replacement. Now what?

That happens often with the older CNT range. It is what the White-Rodgers universal boards are for — the 50A65-5165 covers the 80V ignitor controls and the 50A55-3797 covers the 120V ones. Fitting one is not a compromise when the OEM part no longer exists, but the harness and the configuration matter as much as the board, so bring the old one.

Why does a search for my CNT number find nothing?

Two likely reasons. Either you need the zero — try the five-digit version — or the cross you want is published against the D-number instead. The companies that build these boards catalogue them by their own numbers, not by Trane’s.

Is FAN04073 a fan motor?

No, and this is the most common mis-order on the whole list. FAN is the prefix for fan blades. FAN04073 is a 28-inch three-blade aluminium propeller. A condenser fan motor would carry a MOT number.

Bring the old part in

Open To Public HVAC Parts — 10226 Plano Rd, Suite 104, Dallas, TX. Walk-in counter, open to homeowners and contractors alike since 1998. Bring the part and your unit model number and we will work out what it is with you at the counter, including when the Trane number is nowhere on it.

We stock Trane and Ameristar control boards, defrost boards, ignitors and ignitor kits, flame sensors, inducer assemblies, fan blades, gas valves, limit and pressure switches, plus the White-Rodgers universal boards for the discontinued ones. We test capacitors, contactors, motors, ignitors, relays and transformers free while you wait.

In-store only. We do not ship and we cannot cross parts over the phone.

Sources: Trane 4TWR6 (XR16) product data, model nomenclature section; Trane service part descriptions as republished by Trane distributors; Trane Supply and Trane Technologies support documentation; Copeland/Emerson White-Rodgers installation instructions 37-7516001 (50A65-5165); Jackson Systems and Emerson cross-reference data for 50A55-3797; Supco, Fasco, Packard, US Motors and ICM Controls product literature; Ameristar M4HP and M4AH installation instructions; American Standard product guide; Keith Specialty Trane parts catalog. Verified August 2026.

Related: Control board cross-reference · Ignitor & flame sensor cross-reference · Gas valve cross-reference · Contactor cross-reference · Model number lookup · Furnace short cycling

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