What are the specs for this Transformer?

The correct replacement for Carrier model C50A903064 is this exact part. It is the factory-specified replacement with exact OEM specifications. Using a part with different specifications can cause equipment damage or void your warranty. You can verify this by checking the data plate on your Carrier equipment which lists the model number C50A903064.

Is this transformer compatible with Bryant or Payne systems too?

Many Carrier parts are cross-compatible with Bryant and Payne systems since all three brands are manufactured by Carrier Global Corporation. The same physical part is often used across multiple brand labels with different model numbers. To verify cross-compatibility, check your Bryant or Payne equipment service manual for cross-compatible part numbers, or contact info@nationalhvacparts.com with your model number for confirmation.

Carrier

OEM Carrier Transformer 40VA 120V/24V for C50A903064

Name: OEM Carrier Transformer 40VA 120V/24V for C50A903064
Brand: Carrier
SKU: CARRIE-C50A903064-TRANSFORMER-HT01BD702
Price: 47.25 USD
Availability: InStock

SKU: CARRIE-C50A903064-TRANSFORMER-HT01BD702 Brand: Carrier

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OEM Carrier 40VA Control Transformer HT01BD702 for Model C50A903064

This is the factory OEM replacement transformer (part number HT01BD702) for the Carrier C50A903064 commercial packaged unit. The transformer steps down line voltage from 120V to 24V to power the low-voltage control circuit — including the thermostat, contactor coil, gas valve, and control board. When this transformer fails, the entire control circuit goes dead: the thermostat will show no power, the system won't respond to any call for heating or cooling, and there will be no 24V signal reaching any downstream components. It is often the first component to inspect when a unit appears completely unresponsive.

Specs: 40VA rating | Primary voltage: 120V | Secondary voltage: 24V | OEM part number HT01BD702 | Factory-matched for Carrier C50A903064 packaged units
OEM vs Generic: This OEM transformer is wound and insulated to Carrier's exact specifications, ensuring proper VA capacity and thermal protection. Generic transformers may be under-rated for VA load, leading to premature burnout under high-demand control circuits.
Install difficulty: 2/5 — Disconnect all power before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter to verify 24V output after installation. Label all wire connections before removal. Confirm no short circuit exists in the 24V control wiring before installing the new transformer.
Warranty: 1-year OEM factory warranty against defects in materials and workmanship. In-stock and ships same business day from our warehouse.

Compatibility: Designed as a direct OEM replacement for the Carrier C50A903064 commercial rooftop/packaged unit. Verify your existing transformer's VA rating and primary/secondary voltages against your unit's data plate before ordering. If your original transformer shows signs of burn marks or a blown fuse on the 24V circuit, inspect all downstream wiring for shorts prior to replacement. Have questions about fitment? Our HVAC parts specialists verify compatibility before you order — reach out before you buy.

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

OEM Carrier Transformer 40VA 120...

$47.25

Frequently Asked Questions

Does this Transformer fit my Carrier C50A903064?

Yes. This is the factory-specified OEM transformer for the Carrier C50A903064. 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 C50A903064?

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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OEM Carrier Transformer 40VA 120V/24V for C50A903064

OEM Carrier 40VA Control Transformer HT01BD702 for Model C50A903064

Shipping Information

Return Policy

Frequently Asked Questions