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OEM Carrier Transformer 120V–24V 40VA for PY3PNA024040AB
Carrier

OEM Carrier Transformer 120V–24V 40VA for PY3PNA024040AB

SKU: CARRIE-PY3PNA024040AB-TRANSFORMER-HT01BD209 Brand: Carrier
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Texas CMBL #19328542014
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OEM Carrier Control Transformer 120V–24V 40VA for Model PY3PNA024040AB

This OEM replacement control transformer (part number HT01BD209) is the factory-specified unit for the Carrier PY3PNA024040AB system. The transformer steps down line voltage (120V) to the 24V signal voltage that powers your thermostat, control board, and all low-voltage control circuits. When this part fails, the entire control system goes dark — the thermostat loses power, the system will not respond to any calls for heating or cooling, and no fault codes will display on the board.

  • Specs: Primary voltage: 120V AC | Secondary voltage: 24V AC | VA rating: 40VA | OEM part number: HT01BD209 | Factory-matched construction for Carrier PY3PNA024040AB
  • OEM vs Generic: This is the genuine Carrier OEM transformer, wound to exact VA and voltage specifications. Generic aftermarket transformers often have looser voltage regulation and lower-quality insulation, risking repeated control board failures or nuisance tripping.
  • Install difficulty: 2/5 — Always disconnect power at the breaker before servicing. Tools needed: flat-head and Phillips screwdrivers, needle-nose pliers, multimeter to verify 24V output after installation. Photograph all wiring connections before disconnecting the old transformer.
  • Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Designed as a direct OEM replacement for Carrier model PY3PNA024040AB. Verify your existing transformer's primary/secondary voltage and VA rating on its label before ordering to confirm fitment. Our parts specialists are available to verify compatibility before you buy — order with confidence and get it shipped today.

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 PY3PNA024040AB?
Yes. This is the factory-specified OEM transformer for the Carrier PY3PNA024040AB. 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 PY3PNA024040AB?
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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Mike Rivera
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