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OEM Carrier Transformer 40VA 120V/24V for C50A302551
Carrier

OEM Carrier Transformer 40VA 120V/24V for C50A302551

SKU: CARRIE-C50A302551-TRANSFORMER-HT01BD236 Brand: Carrier
✓ Guaranteed to fit C50A302551 — or your money back. Terms

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Texas CMBL #19328542014
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OEM Carrier Transformer 40VA 120V to 24V for Model C50A302551

This OEM Carrier transformer (part #HT01BD236) is the factory-specified replacement for Carrier C50A302551 commercial packaged units. The transformer steps down 120V line voltage to the 24V low-voltage signal required to power the control board, thermostat, and all 24V control circuit components. When this transformer fails, nothing in the system responds — the thermostat goes dark, the contactor won't energize, and the unit will not start in any mode. It is one of the first components to check when a system is completely unresponsive.

  • Specs: Primary voltage: 120V AC | Secondary voltage: 24V AC | VA rating: 40VA | OEM part number: HT01BD236 | Factory-matched for Carrier C50A302551
  • OEM vs Generic: OEM transformers are wound to exact VA and voltage tolerances, ensuring stable 24V output under full control circuit load. Generic units may sag under load, causing erratic board behavior, nuisance lockouts, and premature control board failure.
  • Install difficulty: 2/5 — Shut off all power before servicing. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or terminal connectors. Confirm 24V output on secondary terminals after installation before closing the unit. Always verify correct wiring polarity.
  • Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier C50A302551 commercial packaged unit. Verify your existing transformer's VA rating and primary/secondary voltages against your unit's data plate before ordering to ensure correct fitment. Need help confirming compatibility? Our HVAC parts specialists verify fitment before you buy — reach out before placing your order.

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 $99
  • 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 C50A302551?
Yes. This is the factory-specified OEM transformer for the Carrier C50A302551. 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 C50A302551?
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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