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OEM Carrier Transformer 40VA 208/240V-24V for PY3PNA042090NA
Carrier

OEM Carrier Transformer 40VA 208/240V-24V for PY3PNA042090NA

SKU: CARRIE-PY3PNA042090NA-TRANSFORMER-HT01BD209 Brand: Carrier
✓ Guaranteed to fit PY3PNA042090NA — or your money back. Terms

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Texas CMBL #19328542014
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OEM Carrier Control Transformer 40VA 208/240V to 24V — Model PY3PNA042090NA

The Carrier HT01BD209 is the factory-specified 40VA control transformer for the PY3PNA042090NA packaged unit. The transformer steps down the line voltage from 208/240V to the 24V signal required by the control board, thermostat, and all low-voltage safety circuits. When this component fails, the entire control circuit goes dark — the thermostat loses communication, the system will not respond to calls for heating or cooling, and no safety fault codes will appear because the board itself has lost power. Replacing it with the correct OEM part restores proper voltage regulation and protects downstream components.

  • Specs: Input 208/240V | Output 24V | Power Rating 40VA | Frequency 50/60Hz | OEM Part # HT01BD209
  • OEM vs Generic: OEM transformers are wound to exact factory VA tolerance, protecting sensitive control boards from voltage fluctuation. Generic aftermarket units may run outside spec, risking premature board failure and voiding system warranties.
  • Install difficulty: 2/5 — Always shut off power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Label all low-voltage wires before disconnecting. Confirm input and output voltage with a meter after installation before restoring full power.
  • Warranty: 1-year OEM manufacturer warranty. In-stock and ships same business day from our warehouse.

Compatibility: Direct OEM replacement for Carrier model PY3PNA042090NA packaged units. Verify 208/240V primary and 24V secondary on your unit's data plate before ordering. Not sure it fits? Our HVAC parts specialists confirm fitment before you buy — contact us today and we'll get your system back online fast.

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 PY3PNA042090NA?
Yes. This is the factory-specified OEM transformer for the Carrier PY3PNA042090NA. 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 PY3PNA042090NA?
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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