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OEM Carrier Transformer 40VA 120V to 24V for C48A405052 — Ships Today
Carrier

OEM Carrier Transformer 40VA 120V to 24V for C48A405052 — Ships Today

SKU: CARRIE-C48A405052-TRANSFORMER-HT01BD236 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier Transformer 40VA 120V/24V for Model C48A405052

This is the factory-specified OEM replacement transformer (part number HT01BD236) for the Carrier C48A405052 packaged unit. The transformer steps down line voltage from 120V to 24V AC to power the entire low-voltage control circuit — including the thermostat, contactor coil, and control board. When this component fails, absolutely nothing in the control system responds: the thermostat goes blank, the system won't call for heating or cooling, and diagnostic LEDs on the control board may go dark entirely.

  • Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01BD236 | Factory-matched output tolerance for stable control voltage
  • OEM vs Generic: This OEM transformer is wound to Carrier's exact VA and voltage specifications. Undersized or off-tolerance generic transformers can sag under load, causing intermittent control lockouts, nuisance tripping, and premature contactor coil failure.
  • Install difficulty: 2/5 — Shut off all power to the unit before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter, wire nuts. Always verify 0V at the primary terminals with a multimeter before handling. Photograph existing wiring connections before removal.
  • Warranty: 1-year OEM factory warranty against defects. In stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier C48A405052 packaged unit. Before ordering, verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate or existing component label. Compatible with the standard 40VA 24V control circuit configuration. Our fitment team is available to confirm compatibility before you order — reach out with your full model and serial number.

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 C48A405052 — Ships Today?
Yes. This is the factory-specified OEM transformer for the Carrier C48A405052 — 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 C48A405052 — 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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