Models
Bryantac

148TAN

Preferred · two-stage condensing unit

Bryant Preferred two-stage air conditioner. Y1/Y2, two-stage scroll, InteliSense on late boards. Not Evolution ABCD and not 187B.

Not 187B (Evolution two-stage, ABCD). Not 191VAN inverter. Not 146SAN / 135SAN (single-stage, one Y).

Stages

Two-stage scroll · Y1 low / Y2 high

Control

24V Y1/Y2. InteliSense when paired

Refrigerant

R-410A on this generation

Sister

Carrier 24TPA7

This board

Preferred two-stage — Y1/Y2, not Evolution drive

  • High stage is Y2 at the outdoor. A single-stage stat never pulls high.
  • InteliSense does not turn this into Evolution ABCD.
  • If you see inverter L-codes, you are on 191VAN.

Live Y1/Y2 and pressures. InteliSense events if equipped.

Universal swap

No universal

Bryant 148TAN outdoor. No furnace IFC universal. Replace the OEM outdoor control / contactor / drive by the silk.

Silk: 148TAN

White-Rodgers

ICM

Honeywell

  • Indoor furnace universals (50A55, 50M56U, ICM282B, ICM2811, S9200U). This is not an IFC.
  • Do not ‘adapt’ a furnace board to an outdoor inverter, defrost PCB, or contactor.

After you pull the dead card

  1. 1Photograph the outdoor silk. Indoor 50A55 / ICM282B / S9200U do not belong here.
  2. 2Contactor units: replace the contactor / cap / HPS — there is no universal outdoor board.
  3. 3Inverter / communicating outdoors: OEM drive only. There is no White-Rodgers or ICM outdoor universal.

Field wiring

Written landings for Bryant 148TAN. Not a factory schematic.

Two-stage 24V · Y1 / Y2
Conventional Y1 / Y2 / CR-410A

Two-stage scroll. High stage is Y2 at the outdoor. A single-stage stat never gets you there. Still not Infinity ABCD.

Written circuit description only — FieldBench does not redraw maker schematics. Example: R to W closes on a heat call; verify 24V at W1 before you change the IFC.

Open manufacturer PDF

This indoor

Preferred Y1/Y2. Not 187B Evolution ABCD.

24V two-stage

Outdoor has Y1 and Y2. Not an inverter drive.

Wall thermostat

Two-stage cool. A single-Y stat never pulls high.

  • R24V hot24V
  • C24V common24V
  • Y1Low-stage cool24V
  • Y2High-stage cool24V
  • GIndoor fan24V
  • WHeat. Stays at the indoor.24V

Indoor IFC / AHU

Y1 and Y2 both have to leave this cabinet on high.

  • RTransformer hot24V
  • CCommon — run it to the outdoor24V
  • Y1Low-stage in / out24V
  • Y2High-stage in / out24V
  • GBlower24V
  • W1Heat24V

Outdoor — Y1 / Y2

Low vs high is these two screws, not an inverter L-code.

  • Y1Low-stage request24V
  • Y2High-stage request24V
  • C24V common24V

Outdoor line

208/230 through the disconnect to the contactor line side.

  • L1LineLine
  • L2LineLine
  • GNDEquipment groundLine

Dual run capacitor

C / FAN / HERM on the can. An inverter outdoor does not have this part.

  • CCommon — both windingsCap
  • FANOutdoor fanCap
  • HERMCompressorCap

Landing

  • 24VIndoor Rstat R · C throughout

    ~24 VAC

  • 24VStat Y1indoor Y1outdoor Y1

    Low-stage coil / request

  • 24VStat Y2indoor Y2outdoor Y2

    High-stage. Missing Y2 = stuck on low.

  • LineL1 / L2disconnect

    208/230

Prove it

  • Y1 at the outdoor on a 1-cool call. Then Y2 on a 2-cool / staging call.
  • If Y2 never arrives, the outdoor is not weak — the stat, indoor IFC, or the Y2 wire is.

Do not

  • Do not hunt ABCD / L-codes. If you see an inverter, you are on 24VNA6 / 191VAN / XV18.
  • InteliSense ≠ Evolution ABCD.

Preferred / Performance / Elite two-stage land here. Bryant 187B Evolution two-stage does not — that one is ABCD.

Sequence

  1. 1

    Y1

    Low-stage compressor.

  2. 2

    Y2

    High-stage. Head and SC should rise.

Faults on this IFC

Step 1, then 2, then 3. Expected reading and the fail branch sit under each check.

HPS

High pressure switch open

lockout

Outdoor HPS opened — coil circuit is dead. Not an inverter pressure fault and not an L-code.

  1. 1 Let it cool, then read the drive LED

    On Bryant 148TAN overcurrent / overheat is often a dirty coil, a failed OD fan, or a locked compressor — not a dead inverter. Clear airflow, confirm the OD fan, and read the drive LED before you order a control. HPS continuity, reset if manual, wiring in series with the coil.

    Expect: OD fan running. Coil clean. Drive LED decoded from THIS outdoor’s card.

  2. 2 Voltage and compressor windings

    Incoming voltage in range (this plate’s line-voltage code). Compressor windings even, no ground. A shorted compressor will kill a new drive. Outdoor airflow: dirty coil, bent fins, fan not running (see ODF / cap).

    Expect: Balanced windings. No winding to ground. Line voltage stable under load.

  3. 3 Charge and the drive last

    A starved or flooded compressor will overcurrent. Confirm SH/SC and charge weight. Only then condemn the inverter. Overcharge or non-condensables — confirm indoor metering before you recover (SH vs SC).

    Expect: Charge on the nameplate. Drive code gone after a cool-down and a clean coil.

ODF

Outdoor fan fail

warn

Fan not turning. Compressor may still run and then HPS.

  1. 1 Heat rejection first

    On Bryant 148TAN high pressure is outdoor airflow until proven otherwise. Fan running the right direction, coil clean, fins not folded, no recirc over a fence or through a garage. Dual-cap FAN section µF vs sticker. A good HERM and a dead FAN is the usual Comfort call.

    Expect: OD fan on, coil clean, discharge air leaving the top/side freely.

  2. 2 Head, subcooling, and liquid line

    Liquid pressure and liquid-line temperature → SC. High head + high SC = overcharge or non-condensables. High head + low SC = restriction or a dying compressor. Do not add gas because suction is low. Fan motor ohms / ground, blade clearance, capacitor wiring (C / FAN / HERM).

    Expect: SC vs the metering device on this plate (TXV ≠ piston).

  3. 3 Restriction vs the switch

    Drier, liquid-line kink, TXV inlet screen, or a non-feed indoor coil will stack head. Ohm / jumper-test the HPS only as a momentary prove, then restore it. A switch that opens on a known-good charge and clean coil is the switch. Not an inverter fan module — there isn’t one.

    Expect: HPS closed at a normal liquid pressure for this refrigerant and OD ambient.

Contactor

Contactor / coil

warn

Will not pull, chatters, or is welded.

  1. 1 Is Y actually at the contactor?

    On Bryant 148TAN a silent outdoor is often no Y. Measure 24 VAC coil-to-C at the contactor on a cool call. 24 VAC at the coil under a Y call. Low voltage = long stat wire, weak indoor transformer, or a furnace 24 (fuse) problem.

    Expect: ~24 VAC at the coil when the indoor is calling.

    If fail: Indoor Y / IFC / stat — not a capacitor.

  2. 2 Cap and the compressor windings

    Dual run cap: herm and fan MFD ±6%. Then windings. A bad cap with a good Y is still the first cheap part — but confirm MFD, do not guess. Coil ohms / burned turns. Pitted or welded points — replace, do not file and leave.

    Expect: MFD on the can. Even windings. Fan and compressor both try.

  3. 3 Contactor and mechanical

    Pitted contactor, no mechanical close, or a welded contactor that never drops out. Replace the failed part; do not file contacts as a repair. Chatter: low 24V, bad coil, weak transformer — not an inverter ramp.

    Expect: Clean pull-in. Line voltage through to both loads.

Cap

Dual run capacitor

warn

HERM and/or FAN section out of rating. Single-stage Comfort dies this way all summer.

  1. 1 Is Y actually at the contactor?

    On Bryant 148TAN a silent outdoor is often no Y. Measure 24 VAC coil-to-C at the contactor on a cool call. Both sections vs microfarad rating, not just one.

    Expect: ~24 VAC at the coil when the indoor is calling.

    If fail: Indoor Y / IFC / stat — not a capacitor.

  2. 2 Cap and the compressor windings

    Dual run cap: herm and fan MFD ±6%. Then windings. A bad cap with a good Y is still the first cheap part — but confirm MFD, do not guess. Bulged can, open bleed, wrong replacement (single vs dual, voltage).

    Expect: MFD on the can. Even windings. Fan and compressor both try.

  3. 3 Contactor and mechanical

    Pitted contactor, no mechanical close, or a welded contactor that never drops out. Replace the failed part; do not file contacts as a repair. Hard-start add-ons do not fix a dead FAN section.

    Expect: Clean pull-in. Line voltage through to both loads.

Charge

Charge (SH piston / SC TXV)

warn

Wrong charge method is as common as wrong charge.

  1. 1 Airflow and freeze before you add gas

    On Bryant 148TAN low pressure / freeze is indoor airflow or a starved coil until proven otherwise. Filter, blower, dirty A-coil, closed supplies. In heat mode, a iced outdoor coil is the same family. Indoor piston: charge by superheat. Indoor TXV: charge by subcooling.

    Expect: Indoor air moving. Coil not iced. OD coil clear in heat.

  2. 2 SH / SC after a thaw

    Thaw fully. Then SH and SC vs the metering device. Low charge ices a piston. A TXV stuck closed ices with high SH. A restriction downstream of the ports fakes a low-charge chart. Do not use Greenspeed weigh-in-only as the only method unless the factory TXV rating plate on THIS outdoor says so. Most 24ACC are piston/TXV conventional.

    Expect: SH/SC in range for this refrigerant and device after a stable 10-minute run.

  3. 3 Leak, TXV, then the LPS

    Weigh-in if the chart says undercharge. Soap / electronic leak on joints and the coil. LPS that opens on a known-good charge and a clear coil is the switch — momentary test only, then restore. Line-set length and indoor coil match still matter. Weigh-in after a repair, then finish on SH or SC.

    Expect: Charge on the nameplate. LPS closed at a normal suction for this OD ambient.

Workflows

148TAN stuck on low

Runs, never cold enough on a design day.

  1. 1 Prove the call and the live code

    Y2 at the outdoor under a 2-cool call.

    Expect: Write whatever Preferred two-stage — Y1/Y2, not Evolution drive is showing. Live Y1/Y2 and pressures. InteliSense events if equipped.

    If fail: No call at the IFC → stat / harness. Do not change gas parts.

  2. 2 Isolate the first failed step in the sequence

    SC on the TXV indoor. Not a 135SAN single-stage shortcut.

    Expect: Y2: High-stage. Head and SC should rise.

  3. 3 Confirm with a number, then the next part

    This is not 187B Evolution. Do not hunt ABCD unless the diagram actually landed it.

    Expect: Contactor coil: Stable ~24 VAC on Y. Chatter = voltage, coil, or HPS. No ABCD to probe. · Dual cap: HERM and FAN both within ~6% (or OEM) of the stamped µF.

    If fail: Stay on this plate. The out-of-range reading is the part.

    If pass: Reading in range → the next step in this workflow is the repair.

Test points

Contactor coil

Stable ~24 VAC on Y. Chatter = voltage, coil, or HPS. No ABCD to probe.

Dual cap

HERM and FAN both within ~6% (or OEM) of the stamped µF.

Charge

SH target on piston indoor; SC target on TXV indoor. Weigh-in is a start, not a Greenspeed-only finish.

HPS

Closed at rest. Open under high head = airflow/charge, not an inverter L-code.

Gotchas

  • 187B is the Evolution two-stage. Wrong chart if the wall control is Evolution.

Related plates

Install this plate

Install Bryant 148TAN as Preferred · two-stage condensing unit.

Preferred · two-stage condensing unit

This plate — not the sister SKU

  • Not 187B (Evolution two-stage, ABCD). Not 191VAN inverter. Not 146SAN / 135SAN (single-stage, one Y).
  • 187B is the Evolution two-stage. Wrong chart if the wall control is Evolution.

Control on this outdoor

  • High stage is Y2 at the outdoor. A single-stage stat never pulls high.
  • InteliSense does not turn this into Evolution ABCD.
  • If you see inverter L-codes, you are on 191VAN.

Hardware

  • Stages: Two-stage scroll · Y1 low / Y2 high
  • Control: 24V Y1/Y2. InteliSense when paired
  • Refrigerant: R-410A on this generation
  • Sister: Carrier 24TPA7

First fire

  1. 1Y2 at the outdoor under a 2-cool call.
  2. 2SC on the TXV indoor. Not a 135SAN single-stage shortcut.
  3. 3This is not 187B Evolution. Do not hunt ABCD unless the diagram actually landed it.

Do not on Bryant 148TAN

  • Not 187B (Evolution two-stage, ABCD). Not 191VAN inverter. Not 146SAN / 135SAN (single-stage, one Y).
  • 187B is the Evolution two-stage. Wrong chart if the wall control is Evolution.

Maker literature

FieldBench does not host manufacturer files. Each link opens the maker’s own literature page in a new tab.

  • Bryant document searchLiterature searchEnter the full Bryant plate (926TB60100V21, 987MA…). Owner PDFs are public; many I/Os are dealer-gated.Open manufacturer PDF
  • Bryant document searchLiterature searchSearch Bryant 148TAN on the maker’s literature page.Open manufacturer PDF

Warranty and bulletins

Affected models, serial range, symptom, remedy, date. Maker files open on the manufacturer site.

All bulletins
  • Residential limited warranty

    warranty sheet

    Carrier / Bryant registered heat-exchanger terms

    Current 59-series / Evolution / Preferred registered warranty · Limited warranty certificate

  • Dealer portals

    dealer

    Where remaining service letters live

    Current-year service letters not on a public literature page · Maker dealer portal