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OEM Carrier Transformer 40VA 120V/24V for C50A503564
Carrier

OEM Carrier Transformer 40VA 120V/24V for C50A503564

SKU: CARRIE-C50A503564-TRANSFORMER-HT01BD702 Brand: Carrier

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Texas CMBL #19328542014
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OEM Carrier Transformer 40VA 120V to 24V for Model C50A503564

This OEM replacement transformer (part number HT01BD702) is the factory-specified control circuit transformer for the Carrier C50A503564 packaged unit. The transformer steps down 120V line voltage to the 24V signal voltage required to power your thermostat, control board, contactor coil, and all low-voltage safety circuits. When this transformer fails, the entire control circuit goes dead — the thermostat displays nothing, the system will not respond to any call for heating or cooling, and your multimeter will read 0V at the secondary terminals.

  • Specs: Primary voltage: 120V AC | Secondary voltage: 24V AC | VA rating: 40VA | OEM part number: HT01BD702 | Replaces factory-installed transformer on Carrier C50A503564 packaged units
  • OEM vs Generic: This OEM unit is wound to exact factory VA and impedance specifications. Undersized or off-tolerance generic transformers can overheat, trip internal thermal fuses prematurely, or deliver unstable 24V output that causes nuisance lockouts and erratic board behavior.
  • Install difficulty: 2/5 — Disconnect power at the breaker and verify zero voltage before starting. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Label or photograph all low-voltage wiring connections prior to removal. The transformer typically mounts to the control panel with two screws and uses push-on or screw-terminal connections on both primary and secondary sides.
  • Warranty: 1-year OEM factory warranty against defects in materials and workmanship. Ships same business day from our warehouse when ordered before cutoff.

Compatibility: Designed specifically for the Carrier C50A503564 commercial packaged rooftop unit. Verify your existing transformer's primary/secondary voltage and VA rating on the data plate or unit wiring diagram before ordering. If your system is experiencing repeated transformer failures, inspect the low-voltage wiring for shorts before installing the replacement. Our fitment team is available to confirm compatibility before you buy — same-day shipping available on in-stock OEM parts.

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 C50A503564?
Yes. This is the factory-specified OEM transformer for the Carrier C50A503564. 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 C50A503564?
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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