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OEM Carrier Transformer 40VA 120V to 24V Control Transformer for C48A302751 | National HVAC Parts
Carrier

OEM Carrier Transformer 40VA 120V to 24V Control Transformer for C48A302751 | National HVAC Parts

SKU: CARRIE-C48A302751-TRANSFORMER-HT01BD236 Brand: Carrier

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier 40VA Control Transformer HT01BD236 for Model C48A302751

This OEM Carrier control transformer (part number HT01BD236) is the factory-specified replacement for the Carrier C48A302751 packaged unit. The transformer steps down line voltage (120V) to the 24V signal used by your thermostat, control board, contactor coil, and every other low-voltage component in the system. When it fails, absolutely nothing works — the thermostat goes dark, the system won't respond to any call for heating or cooling, and you may find a blown fuse on the control board from a secondary short.

  • Specs: 40VA rating | 120V primary | 24V secondary | Factory-matched OEM dimensions and wire gauge | Designed for continuous duty in packaged unit applications
  • OEM vs Generic: OEM Carrier transformers are wound to exact VA and impedance specs for the C48A302751 control circuit. Undersized or off-spec generic units can overheat, blow secondary fuses repeatedly, or damage sensitive control boards — making OEM the smart long-term choice.
  • Install difficulty: 2/5 — Disconnect power at the disconnect box and confirm voltage is zero with a multimeter before touching any wiring. Tools needed: flathead and Phillips screwdriver, multimeter, wire nuts or spade connectors. Photograph all wiring connections before removal.
  • Warranty: 1-year OEM factory warranty against defects. Ships same business day from our in-stock warehouse inventory.

Compatibility: Designed for the Carrier C48A302751 packaged unit. Always verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate before ordering. If you're unsure about fitment, our HVAC parts specialists are available to confirm compatibility before you buy — no guesswork required. Order now and we'll 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 C48A302751 | National HVAC Parts?
Yes. This is the factory-specified OEM transformer for the Carrier C48A302751 | 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 C48A302751 | 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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