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OEM Carrier Transformer 40VA 120V to 24V for C48A306064 | National HVAC Parts
Carrier

OEM Carrier Transformer 40VA 120V to 24V for C48A306064 | National HVAC Parts

SKU: CARRIE-C48A306064-TRANSFORMER-HT01BD702 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier Transformer 40VA 120V to 24V for Model C48A306064

This OEM Carrier transformer (part number HT01BD702) is the factory-specified replacement for the C48A306064 packaged unit. The transformer steps down 120V line voltage to the 24V signal voltage required by your thermostat, contactor coil, and control board. When this component fails, the entire control circuit goes dead — the thermostat shows no power, the system won't respond to any call for heating or cooling, and no components energize. Replacing the transformer is often the first diagnostic step when a unit shows zero control-circuit response.

  • Specs: 40VA rating | 120V primary / 24V secondary | OEM part number HT01BD702 | Factory-matched output tolerance for stable control-circuit voltage
  • OEM vs Generic: OEM transformers are wound to Carrier's exact VA rating and insulation class, ensuring reliable 24V output under full load. Generic units can sag under load, causing erratic thermostat behavior, nuisance lockouts, or premature contactor coil failure.
  • Install difficulty: 2/5 — Shut off all power to the unit before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Document or photograph all wiring connections before disconnecting the old transformer. Verify 24V output with a multimeter after installation.
  • Warranty: 1-year OEM factory warranty. Orders placed before cutoff ship the same business day from our warehouse.

Compatibility: Designed specifically for the Carrier C48A306064 packaged unit. Confirm your unit's data plate lists a 40VA, 120V/24V transformer before ordering. If you are unsure of fitment or have a variant model suffix, contact our parts team — we verify compatibility before you buy.

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 C48A306064 | National HVAC Parts?
Yes. This is the factory-specified OEM transformer for the Carrier C48A306064 | 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 C48A306064 | 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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