FieldBench

Amana

AVPTC

Air handler · ComfortBridge · communicating VS air handler · electric heat

Amana/Goodman ComfortBridge communicating air handler (AVPTC / AVPEC / AHVE family, MBVC modular blower). Serial VS blower and field electric heat strips. No gas valve, no inducer, no furnace E1–E9 pressure-switch codes. CFM and heat-kit staging live in the IFC / CoolCloud menu.

Not a furnace. No E1/E2/E8/E9 draft codes, no HSI, no gas valve. Not AR9T96 / GR9T96 (those are 24V 9-speed furnaces). Pairing this AHU’s data pair to a GR9T96/AR9T96 24V furnace is a mis-pair.

Maker PDFs

Walk this in Diagnose

This plate

Type
Multi-position VS ECM air handler · internal TXV (AVPTC) / EEV on AVPEC
Blower
Communicating variable-speed ECM (serial CFM, no tap plugs)
Heat
Field electric heat kits typically 3–25 kW · sequenced by the IFC, not a furnace gas valve
Control
ComfortBridge indoor control · triple 7-segment + menu buttons + CoolCloud Bluetooth
Tstat
ComfortBridge / communicating preferred · 24V Y/O/W fallback (CFM still from IFC tables)
Pair
Communicating outdoor (GSZC / DSZC / Daikin) or 24V Y1/Y2. Not a 24V 9-speed furnace IFC on the data pair.
Sister SKU
Goodman AVPTC / AVPEC / AHVE · MBVC modular blower (no coil) same control family

This board

ComfortBridge air-handler control · three 7-segment digits + menu buttons

  • Status words (idle, CF, 1AC, 2AC, Htr) are run states, not faults. Htr means electric heat is being staged — not a gas-heat Ht1.
  • Faults that belong here are b-codes (blower/ECM), d0/d4 (memory card), EE (115V / door / internal), electric-heat limit/sequencer, and ComfortBridge data-pair loss. There are no furnace E1–E9 pressure-switch codes on this board.
  • Shared-data memory card is required after a control swap. d0 = empty. d4 = wrong card (furnace card in an AHU, or wrong cabinet size).
  • CoolCloud / on-board menu sets outdoor type, tonnage, and electric-heat kit kW. A heat kit that is installed but not configured will not stage — or will stage with the wrong CFM.
  • 24V fallback (Y/O/W/G) exists. CFM still comes from IFC tables, not tap plugs. Leftover data wires on R/C take the bus down.

Sequence

  1. Call. Communicating stat requests cool, heat-pump heat, or aux. On 24V fallback, Y / O / W at the indoor control. There is no gas sequence.
  2. Blower CFM. IFC looks up CFM from shared-data tables + outdoor type + electric-heat config. Serial ECM ramps. b0/b1 if the motor never runs. b2 if HP does not match the card.
  3. Cool / HP. Outdoor runs from the communicating bus or from 24V Y/O. Indoor is airflow only plus the coil TXV/EEV. A U4/comm outdoor code is the outdoor board, not this chart’s E2.
  4. Electric heat. IFC stages strips through sequencers when aux / emergency / heat-only is requested. Limit on a strip opens that bank. Wrong CoolCloud heat-kit setting is the usual ‘strips on with HP’ or ‘no aux’ complaint.
  5. Satisfied. Strips off, blower off-delay per IFC. No inducer post-purge — there is no inducer.

Faults on this IFC

  • idle / CF / 1AC / 2AC / Htr

    Status, not a fault

    info

    idle = standby. CF = continuous fan. 1AC / 2AC = cooling stage. Htr = electric heat staged. These are run states.

    • Do not replace the board because it says CF or Htr.
    • Htr during a heat-pump call means the IFC thinks aux is needed — check CoolCloud electric-heat / W config before you condemn a sequencer.
  • b0

    ECM blower not running

    lockout

    Indoor control commanded the serial ECM and does not detect it running. No indoor airflow.

    • 14-pin harness at motor and control. No tap plugs.
    • 120 VAC to the motor, wheel free, no wet winding.
    • Do not install an AR9T96 9-speed motor in this air handler.
  • b1

    ECM communications lost

    lockout

    Control cannot talk to the variable-speed blower.

    • 14-pin seated, pins straight, no corrosion.
    • Motor vs control: known-good motor still b1 = indoor control serial driver.
  • b2

    Motor HP mismatch vs shared-data set

    lockout

    Connected motor HP does not match the AHU shared-data set.

    • Wrong replacement motor for this cabinet (AVPTC37 vs 59, etc.).
    • Wrong memory card after a control swap (see d0/d4).
  • b4 / b5

    Motor trip / locked rotor

    lockout

    b4 = lost rotor or overload trip. b5 = locked rotor after 10 start attempts.

    • Wheel rub, debris, seized bearings.
    • Static so high the motor cannot start the wheel.
    • Filter / coil / return before you shotgun the motor.
  • b3 / b9

    Motor limiting / low indoor airflow

    warn

    b3 = folding back on power/speed/temp (reduced CFM). b9 = airflow below calculated minimum.

    • Filter, coil, closed registers, undersized return, TES.
    • CoolCloud tonnage / CFM vs the outdoor and the coil.
    • A communicating motor will ramp into a brick and then b9.
  • d0 / d4

    Shared data / memory card

    lockout

    d0 = replacement control has no shared-data set and cannot drive the ECM or calculate CFM. d4 = card rejected (wrong model).

    • Install the correct AVPTC / AVPEC / AHVE / MBVC card for this cabinet.
    • A furnace AMVC96 or AMVM97 card is d4 in an air handler.
    • Empty tables = silent blower and a ‘no airflow’ call.
  • EE

    No 115V / door / internal

    lockout

    No line voltage reaching the indoor control, door/panel switch open, or internal control condition.

    • Breaker, disconnect, and access panel switch fully made.
    • 115 VAC at the indoor control.
    • If the control is alive and the stat/outdoor is dark, that is the data pair — see Comm.
  • Comm / data pair

    ComfortBridge bus to stat or outdoor

    lockout

    Indoor lost the communicating thermostat or the outdoor on the data pair. Not a furnace E-code. Not 24V Y.

    • Data-pair polarity and splices. Never 24 VAC between the data pins.
    • Only one communicating master.
    • 24V fallback leftover data wires shorted to R/C.
    • A GR9T96 / AR9T96 24V furnace cannot sit on this data pair — that is a mis-pair, not a bad AVPTC board.
  • Electric heat limit / sequencer

    Strip overtemp or sequencer failed

    warn

    A heat-kit limit opened or a sequencer did not bring a bank on. There is no gas-furnace E3 on this machine — this is strip overtemp or a failed sequencer/relay.

    • IFC electric-heat kW matches the installed kit. Wrong CFM on a 20 kW kit opens limits.
    • Filter, coil, static. Strips in a brick duct will limit.
    • Sequencer / relay 24 VAC from the IFC when Htr is displayed. Open limit on that bank = overtemp, not a ‘bad E3 furnace code.’
    • Lugs and element ohms. A failed element is not a control board.

Workflows

No indoor airflow

Blower silent on a cool, HP, or electric-heat call. b0/b1/b2/d0 or nothing.

  1. Photograph the triple display before you pull power. Status vs b-code vs d0 vs EE.
  2. Door/panel switch and 115 VAC at the control (EE). 24V fuse if the display is dead.
  3. d0/d4 after a control swap → correct AVPTC-family memory card, not a furnace card.
  4. 14-pin serial harness. Wheel free. Do not hang a 9-speed tap motor in this cabinet.
  5. TES and filter/coil. b3/b9 are airflow, not a bad motor.
  6. CoolCloud outdoor type and tonnage. Empty or wrong tables command 0 CFM and look like a dead blower.

Heat strips on with heat pump

Htr on the display during a HP heating call, or the bill doubled, or the coil ices because the blower is on strip CFM.

  1. This IFC stages electric heat from CoolCloud / menu config, not from a furnace W2 habit.
  2. Confirm electric-heat kit kW, outdoor type (heat pump, not AC), and aux/balance settings in ComfortBridge.
  3. A kit set as ‘primary heat’ or a W jumper left from a furnace swap will bring strips on with every HP call.
  4. 24V fallback: W at the indoor control is aux. A stat that still closes W on every heat call will run strips.
  5. If Htr is legitimate (aux needed) but a bank is dark, check sequencer 24 VAC and that bank’s limit — not a furnace E3 card.

Mis-pair with GR9T96 / AR9T96

Someone landed this AHU’s data pair on a 24V 9-speed furnace, or is reading furnace E1–E9 on this board.

  1. AVPTC is an air handler. There is no inducer and no pressure switch. Furnace E1–E9 do not exist here.
  2. GR9T96 / AR9T96 cannot be the ComfortBridge indoor. Do not run the data pair to that IFC and expect menus.
  3. Legal pairs: communicating outdoor on the data pair, or 24V Y/O/W/G to a conventional outdoor / furnace. Not both stories at once.
  4. If the job is a furnace + this AHU, the furnace is the heat plant and this AHU should not be in the cabinet. You are on the wrong equipment.
  5. After you land it correctly, set outdoor type and electric heat in CoolCloud. A leftover furnace memory card is d4.

Test points

Data pair
OEM communicating voltage / polarity — never 24 VAC between the data pins.
Motor harness
14-pin serial ECM, fully seated. No tap plugs. No AR9T96 9-speed motor.
Memory card
AVPTC / AVPEC / AHVE / MBVC card for this cabinet. Furnace cards are d4.
Electric heat
CoolCloud kW matches the installed kit. Sequencer 24 VAC when Htr is displayed. Limits closed, elements ohm.
24V fallback
Y / O / W / G at the indoor control if not communicating. CFM still from IFC tables.
Static / CFM
TES vs the AVPTC blower chart for this cabinet and the configured tonnage.

Gotchas

  • Techs look for E2 and an inducer. There is neither. This is an air handler.
  • Electric heat that never runs is usually CoolCloud kit config, not a failed element. Heat that always runs with the HP is the same menu plus a leftover W.
  • MBVC is the modular blower (coil is separate) in the same communicating family. AVPEC adds an EEV. AHVE is the later VS communicating cabinet. Same b/d/EE language.
  • A furnace AMVC96 IFC or memory card in this cabinet will not commission. d0/d4 and a silent blower.
  • Pairing this data pair to AR9T96/GR9T96 is a guaranteed comms call. Those furnaces are 24V only.

Related plates

  • amana-amvc96 — Matching ComfortBridge communicating furnace — gas, inducer, E1–E9. Not this AHU.
  • daikin-dm96vc — Daikin-badge communicating 96% furnace cousin. Same factory communicating indoor idea, different cabinet.
  • goodman-gszc18 — Communicating heat-pump outdoor commonly paired with this AHU. Outdoor codes live on that board, not here.