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OEM Carrier Transformer 40VA 120V/24V for C50A505051
Carrier

OEM Carrier Transformer 40VA 120V/24V for C50A505051

SKU: CARRIE-C50A505051-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 C50A505051

This OEM step-down transformer (part# HT01BD236) is the factory-specified replacement for the Carrier C50A505051 commercial rooftop unit. The transformer converts 120V line voltage down to the 24V signal voltage required to power the control board, thermostat, and all low-voltage system controls. When the transformer fails, the entire control circuit loses power — resulting in a completely unresponsive system, a blank thermostat display, or repeated blown 3-amp fuses on the control board.

  • Specs: 40VA rating | Primary: 120V | Secondary: 24V | Factory-matched impedance | Compatible with multi-stage control circuits
  • OEM vs Generic: OEM transformers are wound to exact VA and impedance specifications for this unit. Undersized or off-spec generic transformers overheat under full control-circuit load, blowing fuses and damaging connected boards.
  • Install difficulty: 2/5 — Shut off all power at the disconnect before servicing. Tools needed: flathead and Phillips screwdriver, multimeter, wire nuts or spade connectors. Verify incoming voltage before connecting. Label all wires prior to disconnecting the original unit.
  • Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier C50A505051 commercial rooftop unit. Always confirm your existing transformer's VA rating and primary/secondary voltages match your unit's data plate specifications before ordering. Our parts team is available to verify fitment — just reach out before you buy. Order today for same-day shipping.

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 C50A505051?
Yes. This is the factory-specified OEM transformer for the Carrier C50A505051. 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 C50A505051?
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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