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OEM Carrier Transformer 40VA 120V to 24V for C48A403064 — Ships Today
Carrier

OEM Carrier Transformer 40VA 120V to 24V for C48A403064 — Ships Today

SKU: CARRIE-C48A403064-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 C48A403064

This OEM control transformer (part number HT01BD702) is the factory-specified replacement for the Carrier C48A403064 packaged unit. The transformer steps down 120V line voltage to the 24V signal voltage required to power the thermostat, control board, contactor coil, and every other low-voltage component in the control circuit. When it fails, the entire control system goes dead — no thermostat response, no fan, no heating or cooling — even though line voltage is present at the unit. A blown transformer is often caused by a short or grounded wire in the 24V circuit, so inspect low-voltage wiring thoroughly before installing the replacement.

  • Specs: 40VA rating | Primary: 120V | Secondary: 24V | OEM part number HT01BD702 | Replaces factory-installed unit with exact plug-and-play fitment
  • OEM vs Generic: This is the genuine Carrier OEM transformer, wound to exact VA and impedance specifications. Off-brand transformers frequently underperform at rated load, causing nuisance tripping, brownouts on the 24V circuit, and premature contactor coil failure.
  • Install difficulty: 2/5 — Disconnect all power before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter (verify 0V before touching terminals), wire nuts or spade terminals. Confirm 24V output after installation before closing the panel.
  • Warranty: 1-year OEM factory warranty. Orders received before cutoff ship same business day from our climate-controlled warehouse.

Compatibility: Engineered for the Carrier C48A403064 packaged unit. Verify your unit's control board accepts a 40VA 24V secondary transformer before ordering — check the data plate inside the control panel access door. Our fitment team is available to confirm compatibility prior to purchase. Order today 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 C48A403064 — Ships Today?
Yes. This is the factory-specified OEM transformer for the Carrier C48A403064 — 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 C48A403064 — 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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