Same-day shipping before 3PM CST · 35,000+ OEM Parts · Texas CMBL & SAM.gov Registered · Government POs Accepted

Menu

Home Shop All Account Cart
OEM Carrier Transformer 40VA 120V-24V for C4850C48ZG055900
Carrier

OEM Carrier Transformer 40VA 120V-24V for C4850C48ZG055900

SKU: CARRIE-C4850C48ZG055900-TRANSFORMER-HT01BD236 Brand: Carrier

OEM Guaranteed

Same-Day Ship

30-Day Returns

Secure Checkout

Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier Control Transformer 40VA 120V/24V for Model C4850C48ZG055900

This is the factory-specified OEM replacement transformer (part number HT01BD236) for the Carrier C4850C48ZG055900 packaged unit. The transformer steps down line voltage from 120V to 24V to power the low-voltage control circuit, including the thermostat, contactor coil, and control board. When the transformer fails, the entire control circuit goes dead — the thermostat loses power, the system won't respond to any calls for heating or cooling, and you may detect a burning odor near the transformer or find the internal fuse blown.

  • Specs: Input 120VAC | Output 24VAC | 40VA rated | OEM part number HT01BD236 | Factory-matched for Carrier C4850C48ZG055900
  • OEM vs Generic: OEM transformers are wound and rated to exact factory specifications, ensuring stable 24V output under full control-circuit load. Generic units may underperform under load, causing erratic contactor chatter and intermittent lockouts.
  • Install difficulty: 2/5 — Disconnect power at the disconnect box and verify zero voltage with a multimeter before starting. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or push-in connectors. Label all low-voltage wiring before removing the old unit.
  • Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed specifically for the Carrier C4850C48ZG055900 packaged unit. Always verify input/output voltage and VA rating against your unit's data plate before ordering. If you need fitment confirmation, our HVAC parts specialists are available to verify compatibility before you purchase — same-day shipping on all in-stock orders.

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 C4850C48ZG055900?
Yes. This is the factory-specified OEM transformer for the Carrier C4850C48ZG055900. 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 C4850C48ZG055900?
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.
Home Shop Search Account Cart
Fitment Guaranteed
MR
Mike Rivera
HVAC Parts Specialist — Online