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OEM Carrier 40VA 120V to 24V Control Transformer for C48A402564 | National HVAC Parts
Carrier

OEM Carrier 40VA 120V to 24V Control Transformer for C48A402564 | National HVAC Parts

SKU: CARRIE-C48A402564-TRANSFORMER-HT01BD702 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier 40VA Control Transformer HT01BD702 for Model C48A402564

This is the factory OEM replacement transformer for the Carrier C48A402564 packaged unit. The transformer steps down 120V line voltage to the 24V signal required by your thermostat, contactor coil, and control board. When this component fails, the entire control circuit goes dark — the thermostat loses power, nothing responds, and the system will not run in any mode. If your Carrier C48A402564 is completely unresponsive and you've ruled out a tripped breaker, a failed transformer is the most likely culprit.

  • Specs: 40VA rating | 120V primary / 24V secondary | OEM part number HT01BD702 | Factory-matched output for full control circuit compatibility
  • OEM vs Generic: This OEM Carrier transformer is wound to exact VA and voltage specifications for the C48A402564. Generic transformers often carry ±15% VA tolerance, which can cause intermittent control failures, nuisance tripping of the secondary fuse, or premature contactor coil burnout.
  • Install difficulty: 2/5 — Always disconnect power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Label all low-voltage wires before disconnecting. Confirm 24V output with your multimeter before restoring the control circuit.
  • Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Direct OEM replacement for Carrier model C48A402564 packaged units. Verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate before ordering. Our HVAC parts specialists are available to confirm fitment prior to purchase — order with confidence and 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 $75
  • 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 C48A402564 | National HVAC Parts?
Yes. This is the factory-specified OEM transformer for the Carrier C48A402564 | National HVAC Parts. 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 C48A402564 | National HVAC Parts?
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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