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OEM Carrier Control Transformer 40VA 208/240V–24V — PY3PNA018040NA
Carrier

OEM Carrier Control Transformer 40VA 208/240V–24V — PY3PNA018040NA

SKU: CARRIE-PY3PNA018040NA-TRANSFORMER-HT01BD209 Brand: Carrier
✓ Guaranteed to fit PY3PNA018040NA — or your money back. Terms

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier Control Transformer 40VA 208/240V to 24V for Model PY3PNA018040NA

This OEM control transformer (part #HT01BD209) is the factory-specified replacement for the Carrier PY3PNA018040NA system. The transformer steps down 208/240V line voltage to 24V to power the low-voltage control circuit — including the thermostat, contactor coil, gas valve, and control board. When it fails, the entire control circuit loses power: the thermostat goes blank, nothing responds, and the system shuts down completely with no error codes.

  • Specs: 208/240V primary | 24V secondary | 40VA rated | 50/60 Hz | Factory-matched OEM tolerances | Also replaces HT01BD207, HT01CN232, and 9076-00
  • OEM vs Generic: OEM transformers are wound to exact VA and voltage tolerances. Undersized or off-tolerance generic units can cause erratic low-voltage behavior, nuisance lockouts, or premature control board failure — especially under full 40VA load conditions.
  • Install difficulty: 2/5 — Turn off all power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade terminals. Photograph existing wiring connections before disconnecting. Verify 24V output with a multimeter after installation before closing the panel.
  • Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Direct OEM replacement for Carrier model PY3PNA018040NA. Also cross-references HT01BD207, HT01CN232, and 9076-00. Verify input voltage (208V or 240V) against your unit's data plate before ordering. Not sure it fits? Our team verifies fitment before you order — contact us and we'll confirm.

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 Control Transformer 40VA 208/240V–24V — PY3PNA018040NA?
Yes. This is the factory-specified OEM transformer for the Carrier OEM Carrier Control Transformer 40VA 208/240V–24V — PY3PNA018040NA. 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 Control Transformer 40VA 208/240V–24V — PY3PNA018040NA?
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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