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OEM Carrier 40VA 120V to 24V Control Transformer for C48A203064 — Ships Today
Carrier

OEM Carrier 40VA 120V to 24V Control Transformer for C48A203064 — Ships Today

SKU: CARRIE-C48A203064-TRANSFORMER-HT01BD702 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier Control Circuit Transformer 40VA for Model C48A203064

This OEM replacement transformer (part number HT01BD702) is the factory-specified step-down transformer for the Carrier C48A203064 packaged unit. The transformer converts 120V line voltage to the 24V signal required to power your control board, thermostat, contactor coil, and all low-voltage control circuits. When this component fails, the entire control system goes dark — the thermostat becomes unresponsive, the unit will not start, and no error codes can be generated because the board itself has lost power.

  • Specs: 40VA rating | Primary: 120V | Secondary: 24V | OEM Part Number: HT01BD702 | Factory-matched impedance and thermal protection
  • OEM vs Generic: This OEM Carrier transformer is wound to exact factory VA ratings, ensuring the 24V secondary circuit can handle full control-board and contactor coil loads simultaneously. Undersized or off-tolerance generic transformers can overheat, trip thermal cutoffs repeatedly, or fail prematurely under multi-zone thermostat loads.
  • Install difficulty: 2/5 — Disconnect all power before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Photograph all wiring connections before removal. Verify input and output voltages with a multimeter after installation before closing the panel.
  • Warranty: 1-year OEM factory warranty. Orders placed before cutoff ship same business day from our climate-controlled warehouse.

Compatibility: Designed for the Carrier C48A203064 packaged unit. Always verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate or wiring diagram before ordering. Our HVAC parts specialists are available to confirm fitment — reach out before you order if you have any questions. In stock and ready to ship 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 $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 C48A203064 — Ships Today?
Yes. This is the factory-specified OEM transformer for the Carrier C48A203064 — Ships Today. 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 C48A203064 — Ships Today?
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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