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OEM Carrier Transformer 40VA 120V/24V for C50A503064
Carrier

OEM Carrier Transformer 40VA 120V/24V for C50A503064

SKU: CARRIE-C50A503064-TRANSFORMER-HT01BD702 Brand: Carrier

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier 40VA Control Transformer HT01BD702 for Model C50A503064

This OEM step-down transformer (part# HT01BD702) is the factory-specified replacement for the Carrier C50A503064 commercial packaged unit. The transformer converts 120V line voltage to the 24V AC signal that powers your thermostat, control board, contactor coil, and every other low-voltage component in the control circuit. When this transformer fails, absolutely nothing works — the thermostat goes dark, the system won't respond to any call for heating or cooling, and you may blow a control fuse repeatedly. It is often the first component to check in a complete system-down scenario.

  • Specs: 40VA rating | 120V primary / 24V secondary | Single-phase | Factory-matched impedance and thermal protection for reliable low-voltage output
  • OEM vs Generic: OEM transformers from Carrier are wound to exact VA and voltage tolerances. Generic units may deliver unstable 24V output, causing nuisance trips, contactor chatter, or premature control board failure — making the OEM choice the smarter long-term investment.
  • Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Photograph all wiring connections before removal. Verify 24V output at secondary terminals after installation before closing the cabinet.
  • Warranty: 1-year OEM factory warranty against defects. Ships same business day from our warehouse when ordered before cutoff.

Compatibility: Designed for the Carrier C50A503064 commercial rooftop/packaged unit. Always verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate or wiring diagram before ordering. Our HVAC parts specialists are available to confirm fitment — just reach out before you buy. Order now and your part ships today.

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 C50A503064?
Yes. This is the factory-specified OEM transformer for the Carrier C50A503064. 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 C50A503064?
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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