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OEM Carrier Transformer 40VA 120V to 24V for C4850C50AW02561 — Ships Today
Carrier

OEM Carrier Transformer 40VA 120V to 24V for C4850C50AW02561 — Ships Today

SKU: CARRIE-C4850C50AW02561-TRANSFORMER-HT01BD236 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier 40VA Control Transformer HT01BD236 for Model C4850C50AW02561

This OEM step-down transformer (part number HT01BD236) is the factory-specified replacement for the Carrier C4850C50AW02561 packaged unit. The transformer converts 120V line voltage to the 24V signal required by your thermostat, control board, contactor coil, and all low-voltage control circuits. When this component fails, the entire control system goes dark — your thermostat displays nothing, the unit won't respond to any commands, and no heating or cooling cycle can initiate. If you've verified your thermostat and control board are intact but the system is completely unresponsive, a failed transformer is the most likely culprit.

  • Specs: 40VA rating | Primary: 120V | Secondary: 24V | OEM part number HT01BD236 | Factory-matched output tolerance for stable control circuit operation
  • OEM vs Generic: This OEM unit is wound to Carrier's exact VA rating and insulation class. Generic transformers frequently run under-rated VA loads, causing premature overheating, blown fuses on the secondary side, and nuisance control board faults that are difficult to diagnose.
  • Install difficulty: 2/5 — Disconnect power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter (confirm 24V output after install). Photograph all wiring connections before disconnecting. Secondary fuse (typically 3A) should also be inspected and replaced if blown.
  • Warranty: 1-year OEM factory warranty. In-stock and ships the same business day from our warehouse.

Compatibility: Designed specifically for the Carrier C4850C50AW02561 packaged unit. Verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate before ordering to ensure a direct match. Our parts specialists are available to confirm fitment — order with confidence and get your system back online fast.

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 C4850C50AW02561 — Ships Today?
Yes. This is the factory-specified OEM transformer for the Carrier C4850C50AW02561 — Ships Today. 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 C4850C50AW02561 — Ships Today?
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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