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OEM Carrier Transformer 40VA 120V-24V for C4850C48ZG035500
Carrier

OEM Carrier Transformer 40VA 120V-24V for C4850C48ZG035500

SKU: CARRIE-C4850C48ZG035500-TRANSFORMER-HT01BD236 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier Transformer 40VA 120V to 24V for Model C4850C48ZG035500

This OEM replacement transformer (part# HT01BD236) is the factory-specified 24V control circuit transformer for the Carrier C4850C48ZG035500 packaged unit. The transformer steps down line voltage (120V) to the 24V AC signal that powers your thermostat, control board, contactor coil, and all low-voltage control components. When the transformer fails, the entire control circuit goes dead — the thermostat goes blank, the system won't respond to any calls for heating or cooling, and no components will energize. This is one of the first components to check when a unit presents with a completely unresponsive control circuit.

  • Specs: 40VA rating | 120V primary / 24V secondary | Factory OEM part number HT01BD236 | Direct plug-and-play wiring match for C4850C48ZG035500
  • OEM vs Generic: The OEM HT01BD236 transformer is wound to exact VA and voltage tolerances required by Carrier's control board. Undersized or off-tolerance generic transformers can cause erratic board behavior, nuisance tripping, or premature board failure — making OEM the only recommended choice for this application.
  • Install difficulty: 2/5 — Disconnect power at the disconnect box before beginning. Tools needed: flathead and Phillips screwdriver, needle-nose pliers, multimeter. Label all low-voltage wires before removing. Verify 24V output with a multimeter after installation and before restoring full power.
  • Warranty: 1-year OEM factory warranty. Orders placed by 3PM local time ship same business day from our warehouse.

Compatibility: Designed for the Carrier C4850C48ZG035500 packaged unit. Verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate before ordering to confirm fitment. Our parts specialists are available to verify compatibility — reach out before you order if you have any questions.

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 C4850C48ZG035500?
Yes. This is the factory-specified OEM transformer for the Carrier C4850C48ZG035500. 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 C4850C48ZG035500?
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
HVAC Parts Specialist — Online