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OEM Carrier Transformer 40VA 120V/24V for C48A802064 — HT01BD702
Carrier

OEM Carrier Transformer 40VA 120V/24V for C48A802064 — HT01BD702

SKU: CARRIE-C48A802064-TRANSFORMER-HT01BD702 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier Control Transformer 40VA 120V/24V for Model C48A802064

This is the OEM factory-replacement control transformer (part number HT01BD702) for the Carrier C48A802064 packaged unit. The transformer steps down 120V line voltage to the 24V signal used by your thermostat, contactor coil, and control board. When it fails, the entire low-voltage control circuit goes dead — the thermostat goes blank, the system won't respond to any call for heating or cooling, and nothing turns on. It is one of the first components to check when a system appears completely unresponsive despite having line power.

  • Specs: Input 120V AC | Output 24V AC | 40VA rating | OEM part number HT01BD702 | Factory-matched primary and secondary windings for precise voltage regulation
  • OEM vs Generic: This is the genuine Carrier OEM transformer, wound to exact factory VA and voltage specifications. Generic transformers often underrate their VA capacity, causing overheating and premature failure — especially when multiple 24V accessories (humidifier, zone board, UV light) share the same circuit.
  • Install difficulty: 2/5 — Disconnect all power before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Confirm primary voltage at the transformer terminals before condemning the part. Always cap or tape wire ends during replacement to prevent accidental shorts.
  • Warranty: 1-year OEM factory warranty against defects. Ships same business day from our stocked warehouse.

Compatibility: Designed for the Carrier C48A802064 packaged unit. Verify your unit's control voltage requirements and existing transformer VA rating on the data plate before ordering. If you are unsure of fitment, our parts team is available to confirm compatibility before you buy. In stock and ready to ship today — 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 C48A802064 — HT01BD702?
Yes. This is the factory-specified OEM transformer for the Carrier C48A802064 — HT01BD702. 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 C48A802064 — HT01BD702?
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
HVAC Parts Specialist — Online