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OEM Carrier Furnace Transformer 120V-24V 40VA — PG8UAA042091ABJA
Carrier

OEM Carrier Furnace Transformer 120V-24V 40VA — PG8UAA042091ABJA

SKU: CARRIE-PG8UAA042091ABJA-TRANSFORMER-HT01BC116 Brand: Carrier
✓ Guaranteed to fit PG8UAA042091ABJA — or your money back. Terms

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OEM Carrier Furnace Transformer 120V–24V 40VA for Model PG8UAA042091ABJA

This OEM step-down transformer is the factory-specified replacement for the Carrier PG8UAA042091ABJA gas furnace. The transformer converts 120V line voltage to 24V AC to power the furnace's entire low-voltage control circuit — including the thermostat, control board, gas valve, and zone controls. When this part fails, nothing in the furnace responds: no ignition attempt, no blower, no call-for-heat reaction. If you measure 0V between the R and C terminals on your control board, a failed transformer is the first thing to replace.

  • Specs: Primary voltage: 120V AC | Secondary voltage: 24V AC | VA rating: 40VA | Frequency: 60 Hz | Single phase | Foot-mount configuration | Wire lead connections with insulated female quick-connect terminals
  • OEM vs Generic: This OEM transformer is built to exact Carrier factory tolerances. Generic transformers frequently use lighter-gauge windings and lower-rated cores that run hot, blow fuses prematurely, or fail to sustain the 24V output under full system load — especially with multi-zone setups or added accessories.
  • Install difficulty: 2/5 — Shut off all power to the furnace at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph all wiring connections before disconnecting. Mount the new transformer to the existing bracket and reconnect leads to matching terminals. Verify 24V output at R–C before closing the cabinet.
  • Warranty: 1-year OEM manufacturer warranty. In stock — ships same business day from our warehouse.

Compatibility: Direct OEM replacement for Carrier model PG8UAA042091ABJA gas furnace. This part supersedes and replaces original part number HT01BC116, as well as HT01BC115, HT01BB126, HT01CT120, HT01BC120, and several other legacy Carrier/Bryant transformer part numbers. Verify your unit's data plate shows a 120V primary supply before ordering. Have questions about fitment? Our HVAC parts specialists confirm compatibility before you buy — order with confidence and get same-day shipping.

Shipping Information

  • Orders placed before 3PM CST ship same business day
  • Standard delivery: 2-5 business days
  • Express shipping available at checkout
  • Free shipping on orders over $99
  • Tracking number emailed upon shipment

Return Policy

  • 30-day returns on unused parts in original packaging
  • Electrical parts (capacitors, contactors, control boards) are final sale once installed
  • Email info@nationalhvacparts.com to initiate a return
  • Refunds processed within 5-7 business days

Frequently Asked Questions

Does this Transformer fit my Carrier OEM Carrier Furnace Transformer 120V-24V 40VA — PG8UAA042091ABJA?
Yes. This is the factory-specified OEM transformer for the Carrier OEM Carrier Furnace Transformer 120V-24V 40VA — PG8UAA042091ABJA. It is a direct drop-in replacement that fits without modification. Always verify the model number on your equipment nameplate before ordering.
How do I replace the transformer on my Carrier OEM Carrier Furnace Transformer 120V-24V 40VA — PG8UAA042091ABJA?
Difficulty: Medium (30–45 min)
Step 1: Turn off breaker. Step 2: Photo wiring connections. Step 3: Disconnect wires from old transformer. Step 4: Remove mounting hardware. Step 5: Install new transformer, reconnect wires matching voltage ratings. Step 6: Verify 24V output with multimeter.
My thermostat has no power. What failed?
Thermostat with no display = failed 24V transformer (or blown control board fuse). Check the 3A/5A fuse on the control board first ($1–$5 fix). If fuse is good but no 24V output from transformer, replace transformer.
Is this transformer compatible with Bryant or Payne too?
Many Carrier parts are cross-compatible with Bryant and Payne since all three brands are manufactured by Carrier Global Corporation. The same physical part is often used across brand labels with different model numbers. To verify: check your Bryant or Payne equipment service manual for cross-compatible part numbers, or email info@nationalhvacparts.com with your model number.
Should I use OEM or aftermarket for my Carrier transformer?
OEM recommended for reliability and warranty compatibility. OEM parts match exact factory specifications for proper fit, performance, and safety. While aftermarket alternatives cost less upfront, the risk of improper fit and reduced lifespan usually makes OEM the better value long-term.
How fast does National HVAC Parts ship?
Orders placed before 3:00 PM CST ship the same business day. Standard delivery is 2–5 business days anywhere in the continental United States. Express shipping available at checkout. We ship from Houston, TX to all 50 states. 30-day return policy on all parts.
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