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OEM Carrier Transformer 40VA 120V/24V for C50A504064
Carrier

OEM Carrier Transformer 40VA 120V/24V for C50A504064

SKU: CARRIE-C50A504064-TRANSFORMER-HT01BD702 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier Control Transformer 40VA 120V/24V for Model C50A504064

This is the factory OEM replacement control transformer (part number HT01BD702) for the Carrier C50A504064 commercial rooftop unit. The transformer steps down line voltage from 120V to 24V to power the low-voltage control circuit — including the thermostat, contactor coil, and all safety controls. When this transformer fails, absolutely nothing in the control system responds: the thermostat goes dark, the unit won't energize, and no staging commands are executed. It is often the first component to diagnose when facing a completely unresponsive unit.

  • Specs: 40VA rating | Primary: 120V | Secondary: 24V | OEM part number HT01BD702 | Factory-matched control circuit output
  • OEM vs Generic: OEM transformers are wound and rated to exact factory specifications, ensuring stable 24V output under full control-circuit load. Generic alternatives frequently deliver undervoltage under peak demand, causing nuisance lockouts, erratic staging, and premature contactor coil failure.
  • Install difficulty: 2/5 — Disconnect all power before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade terminals. Verify primary and secondary voltages with a multimeter before and after replacement. Always label or photograph wiring connections prior to removal.
  • Warranty: 1-year OEM factory warranty against defects. Orders placed before cutoff ship same business day from our warehouse.

Compatibility: Designed specifically for the Carrier C50A504064 commercial rooftop packaged unit. Verify your existing transformer's VA rating and primary/secondary voltages against your unit's data plate before ordering. Our fitment team is available to confirm compatibility before you buy — same-day shipping available on all 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 C50A504064?
Yes. This is the factory-specified OEM transformer for the Carrier C50A504064. 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 C50A504064?
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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