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OEM Carrier Transformer 40VA 120V to 24V for C48A402561 HT01BD236 | National HVAC Parts
Carrier

OEM Carrier Transformer 40VA 120V to 24V for C48A402561 HT01BD236 | National HVAC Parts

SKU: CARRIE-C48A402561-TRANSFORMER-HT01BD236 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 C48A402561 — HT01BD236

This OEM control transformer (part number HT01BD236) is the factory-specified replacement for the Carrier C48A402561 packaged unit. The transformer steps down 120V line voltage to the 24V AC signal required by the thermostat, control board, contactor coil, and all low-voltage control circuits. When this transformer fails, the entire control circuit loses power — the thermostat goes blank, the system won't respond to any call for heating or cooling, and nothing operates. It is often the first component to inspect when a unit is completely unresponsive despite confirmed line voltage at the unit.

  • Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | Factory OEM part number HT01BD236 | Drop-in replacement with original mounting configuration
  • OEM vs Generic: OEM transformers are wound to exact VA and voltage tolerances required by Carrier's control boards. Undersized or off-tolerance generic units can cause erratic low-voltage behavior, nuisance tripping, or premature control board damage.
  • Install difficulty: 2/5 — Disconnect all power before servicing. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (verify 0V before touching terminals). Label all low-voltage wires before disconnecting. Verify 24V output after installation before closing the cabinet.
  • Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Engineered specifically for the Carrier C48A402561 packaged unit. Always verify your existing transformer's VA rating and primary/secondary voltages against your unit's data plate before ordering. Our HVAC parts specialists are available to confirm fitment — contact us before you order if you have any questions.

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 C48A402561 HT01BD236 | National HVAC Parts?
Yes. This is the factory-specified OEM transformer for the Carrier C48A402561 HT01BD236 | 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 C48A402561 HT01BD236 | 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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