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OEM Carrier Transformer 40VA 120V to 24V for C4850C48ZN030200 — Ships Today
Carrier

OEM Carrier Transformer 40VA 120V to 24V for C4850C48ZN030200 — Ships Today

SKU: CARRIE-C4850C48ZN030200-TRANSFORMER-HT01BD236 Brand: Carrier

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier 40VA Control Transformer HT01BD236 for Model C4850C48ZN030200

This OEM replacement transformer (part number HT01BD236) is the factory-specified 120V-to-24V step-down transformer for the Carrier C4850C48ZN030200 packaged unit. The transformer powers the entire 24V control circuit — including the thermostat, contactor coil, and control board. When it fails, absolutely nothing responds: the thermostat goes dark, the system won't call for heating or cooling, and the unit sits completely unresponsive despite power being present at the disconnect.

  • Specs: Primary voltage: 120V AC | Secondary voltage: 24V AC | VA rating: 40VA | OEM part number: HT01BD236 | Factory-matched construction for Carrier C4850C48ZN030200
  • OEM vs Generic: This OEM unit is wound to exact VA and insulation class specifications. Generic transformers often underrate their VA capacity, causing premature thermal cutout trips and nuisance lockouts — especially under high-demand control circuit loads.
  • Install difficulty: 2/5 — Disconnect power at the unit disconnect and verify zero voltage before proceeding. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade terminals. Label all wiring connections before removal. Primary wires connect to line voltage; secondary wires feed the 24V control circuit — do not reverse.
  • Warranty: 1-year OEM factory warranty against defects. Orders placed before cutoff ship same business day from our climate-controlled warehouse.

Compatibility: Designed specifically for the Carrier C4850C48ZN030200 packaged unit. Confirm 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 verify fitment — contact us before you buy if you have any questions. In stock and ready to ship 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 C4850C48ZN030200 — Ships Today?
Yes. This is the factory-specified OEM transformer for the Carrier C4850C48ZN030200 — 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 C4850C48ZN030200 — 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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