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OEM Carrier 40VA 120V to 24V Transformer for C48A404052 — Ships Today
Carrier

OEM Carrier 40VA 120V to 24V Transformer for C48A404052 — Ships Today

SKU: CARRIE-C48A404052-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 C48A404052

This OEM control transformer (part number HT01BD236) is the factory-specified replacement for the Carrier C48A404052 packaged unit. The transformer steps down line voltage from 120V to 24V to power the entire low-voltage control circuit — including the thermostat, contactor coil, and control board. When this part fails, the result is complete loss of control power: the thermostat goes blank, the system won't respond to any calls for heating or cooling, and nothing operates. It is one of the first components to check when a unit appears completely unresponsive.

  • Specs: 40VA rating | 120V primary / 24V secondary | OEM part number HT01BD236 | Factory-matched for Carrier C48A404052 packaged units
  • OEM vs Generic: OEM transformers are wound to exact VA tolerances and insulated to factory specifications. Undersized or off-tolerance generic units can overheat under full control circuit load, blow fuses, or damage sensitive control boards.
  • Install Difficulty: 2/5 — Shut off all power before servicing. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Always confirm primary and secondary voltages with a meter before and after installation to protect downstream components.
  • Warranty: 1-year OEM factory warranty. Orders received before cutoff ship same business day from our stocked warehouse.

Compatibility: Designed for the Carrier C48A404052 packaged unit. Verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate or wiring diagram before ordering. Our fitment team is available to confirm compatibility before you purchase — 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 C48A404052 — Ships Today?
Yes. This is the factory-specified OEM transformer for the Carrier C48A404052 — Ships Today. 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 C48A404052 — Ships Today?
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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