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OEM Carrier Transformer 40VA 120V to 24V for C4850C50AY03061 — Ships Today
Carrier

OEM Carrier Transformer 40VA 120V to 24V for C4850C50AY03061 — Ships Today

SKU: CARRIE-C4850C50AY03061-TRANSFORMER-HT01BD236 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier 40VA Control Transformer for Model C4850C50AY03061

This OEM replacement transformer (part# HT01BD236) is the factory-specified control circuit transformer for the Carrier C4850C50AY03061 packaged unit. The transformer steps down 120V line voltage to the 24V AC signal that powers your thermostat, control board, contactor coil, and all low-voltage safety circuits. When this component fails, the entire control circuit goes dark — the thermostat becomes unresponsive, the system will not stage heating or cooling, and you may find a blown 3A fuse on the control board as a secondary symptom. Replacing the transformer is one of the most cost-effective repairs in the system.

  • Specs: 40VA rated | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01BD236 | Factory-matched winding insulation class
  • OEM vs Generic: The OEM HT01BD236 transformer meets Carrier's exact VA rating and insulation class. Undersized or off-brand transformers are prone to thermal overload when multiple low-voltage accessories (humidifiers, zoning boards, UV lights) share the circuit, leading to premature failure and potential control board damage.
  • Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before starting. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Verify 24V output after installation before restoring full system power. Photograph all wiring connections before disconnecting.
  • Warranty: 1-year OEM factory warranty against defects. In stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier C4850C50AY03061 packaged unit. Always verify the 40VA rating and primary/secondary voltages against your unit's wiring diagram before ordering — VA rating must match or exceed the original to avoid overload. Our fitment specialists are available to confirm compatibility before you purchase. Order today and enjoy same-day shipping 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 C4850C50AY03061 — Ships Today?
Yes. This is the factory-specified OEM transformer for the Carrier C4850C50AY03061 — 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 C4850C50AY03061 — 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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