Same-day shipping before 3PM CST · 35,000+ OEM Parts · Texas CMBL & SAM.gov Registered · Government POs Accepted

Menu

Home Shop All Account Cart
OEM Carrier 40VA 120V to 24V Control Transformer for C48A402761 (HT01BD236) | National HVAC Parts
Carrier

OEM Carrier 40VA 120V to 24V Control Transformer for C48A402761 (HT01BD236) | National HVAC Parts

SKU: CARRIE-C48A402761-TRANSFORMER-HT01BD236 Brand: Carrier

OEM Guaranteed

Same-Day Ship

30-Day Returns

Secure Checkout

Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier Control Transformer 40VA 120V/24V for Model C48A402761

This OEM replacement transformer (part number HT01BD236) is the factory-specified control circuit transformer for the Carrier C48A402761 packaged unit. The transformer steps down 120V line voltage to the 24V signal voltage required to power the thermostat, control board, contactors, and all low-voltage switching components. When this transformer fails, the entire control circuit loses power — the result is a completely unresponsive system with no heating, no cooling, and no thermostat communication whatsoever.

  • Specs: 40VA rating | Primary: 120V | Secondary: 24V | OEM part number HT01BD236 | Factory-matched to Carrier C48A402761 control circuit requirements
  • OEM vs Generic: This is the genuine OEM Carrier transformer, wound to exact factory VA and voltage tolerances. Generic transformers frequently fall short of the rated 40VA output under load, causing nuisance lockouts, erratic control board behavior, and premature contactor coil burnout.
  • Install difficulty: 2/5 — Disconnect power at the breaker and verify zero voltage before beginning. Tools needed: flathead and Phillips screwdrivers, wire nuts or spade connectors, multimeter for output verification. Always confirm 24V output at secondary terminals before reconnecting the control circuit.
  • Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed specifically for the Carrier C48A402761 packaged unit. Confirm your existing transformer's VA rating and primary/secondary voltages on the unit data plate before ordering. If you're unsure of fitment, our HVAC parts specialists can verify compatibility before your order ships — same-day shipping available on all in-stock OEM parts.

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 C48A402761 (HT01BD236) | National HVAC Parts?
Yes. This is the factory-specified OEM transformer for the Carrier C48A402761 (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 C48A402761 (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.
Home Shop Search Account Cart
Fitment Guaranteed
MR
Mike Rivera
HVAC Parts Specialist — Online