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OEM Carrier 40VA 120V to 24V Control Transformer for C48A403051 | National HVAC Parts
Carrier

OEM Carrier 40VA 120V to 24V Control Transformer for C48A403051 | National HVAC Parts

SKU: CARRIE-C48A403051-TRANSFORMER-HT01BD236 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier 40VA Control Transformer HT01BD236 for Model C48A403051

This is the factory OEM replacement transformer (part number HT01BD236) for the Carrier C48A403051 packaged unit. The transformer steps down line voltage from 120V to 24V to power the low-voltage control circuit — including the thermostat, contactor coil, and control board. When the transformer fails, the entire control circuit goes dead: the thermostat loses power, the system won't respond to calls for heating or cooling, and there are no error codes because the board itself has no power to display them.

  • Specs: Input 120V AC | Output 24V AC | 40VA rating | OEM part number HT01BD236 | Factory-matched construction for drop-in replacement
  • OEM vs Generic: OEM transformers are wound to exact VA and voltage tolerances for the C48A403051 control circuit. Generic units may under-deliver VA under load, causing nuisance brownouts, contactor chatter, or premature board failure.
  • Install difficulty: 2/5 — Disconnect power at the disconnect box before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Label or photograph all low-voltage wiring before disconnecting. Verify 24V output at secondary terminals with a multimeter after installation before restoring full power.
  • Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed as a direct OEM replacement for the Carrier C48A403051 packaged unit. Always confirm transformer VA rating and primary/secondary voltages on your unit's data plate before ordering. Our parts specialists are available to verify fitment prior to purchase — order with confidence 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 C48A403051 | National HVAC Parts?
Yes. This is the factory-specified OEM transformer for the Carrier C48A403051 | 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 C48A403051 | 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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