Same-day shipping before 3PM CST · 35,000+ OEM Parts · Texas CMBL & SAM.gov Registered · Government POs Accepted

Menu

Home Shop All Account Cart
OEM Carrier Transformer 40VA 120V to 24V Control Transformer for C48A302564 | National HVAC Parts
Carrier

OEM Carrier Transformer 40VA 120V to 24V Control Transformer for C48A302564 | National HVAC Parts

SKU: CARRIE-C48A302564-TRANSFORMER-HT01BD702 Brand: Carrier

OEM Guaranteed

Same-Day Ship

30-Day Returns

Secure Checkout

Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier 40VA Control Transformer HT01BD702 for Model C48A302564

This OEM step-down transformer (part number HT01BD702) is the factory-specified replacement for the Carrier C48A302564 packaged unit. The transformer converts 120V line voltage to 24V AC to power the low-voltage control circuit — including the thermostat, contactor coil, and control board. When this part fails, the entire control system loses power: the thermostat goes blank, the unit won't respond to any calls for heating or cooling, and no fault codes will display. It is one of the first components to check when a unit appears completely unresponsive despite having line voltage present.

  • Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01BD702 | Factory-matched output tolerances for reliable low-voltage circuit operation
  • OEM vs Generic: This OEM transformer is wound to Carrier's exact VA rating and voltage tolerances. Undersized or off-tolerance generic transformers can overheat, trip thermal protection, or deliver insufficient voltage to reliably pull in contactors and energize control boards.
  • Install difficulty: 2/5 — Disconnect power at the disconnect box before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or terminal connectors. Label or photograph all low-voltage wiring before disconnecting. Confirm 24V output with a multimeter after installation before restoring full power.
  • Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier C48A302564 packaged unit. Verify your existing transformer's VA rating and primary/secondary voltage on the unit's data plate or wiring diagram before ordering. Our team is available to confirm fitment prior to purchase — don't hesitate to reach out. Order today and receive same-day shipping on all in-stock parts.

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 C48A302564 | National HVAC Parts?
Yes. This is the factory-specified OEM transformer for the Carrier C48A302564 | 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 C48A302564 | 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.
Home Shop Search Account Cart
Fitment Guaranteed
MR
Mike Rivera
HVAC Parts Specialist — Online