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 to 24V for C4850C50ZN055500 — Ships Today
Carrier

OEM Carrier Transformer 40VA 120V to 24V for C4850C50ZN055500 — Ships Today

SKU: CARRIE-C4850C50ZN055500-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 Transformer 40VA 120V to 24V for Model C4850C50ZN055500

This OEM replacement transformer (part number HT01BD236) is the factory-specified control circuit transformer for the Carrier C4850C50ZN055500 packaged unit. The transformer steps line voltage (120V) down to the 24V signal voltage required to power the control board, thermostat circuit, and all low-voltage system controls. When this component fails, the entire control circuit goes dead — the thermostat loses communication, the unit will not respond to any calls for heating or cooling, and no safety outputs will function. A failed transformer is often misdiagnosed as a control board failure, making correct identification critical before replacing more expensive components.

  • Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01BD236 | Factory-matched for Carrier C4850C50ZN055500
  • OEM vs Generic: This OEM transformer is wound to exact factory VA and voltage specifications. Generic transformers may be under-rated in VA capacity, causing overheating and premature failure when the 24V circuit draws full load during defrost or multi-stage operation.
  • Install difficulty: 2/5 — Disconnect power at the disconnect box and verify zero voltage with a multimeter before proceeding. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter, needle-nose pliers. Check for a blown 3A fuse on the secondary side before condemning the transformer — a shorted zone valve or thermostat wire can blow the secondary circuit.
  • Warranty: 1-year OEM factory warranty against defects. Orders received by 3 PM local time ship same business day from our HVAC-dedicated warehouse.

Compatibility: Designed specifically for the Carrier C4850C50ZN055500 packaged unit. Verify your existing transformer's VA rating and primary/secondary voltages on the data plate before ordering. If you are unsure of fitment, our parts specialists can confirm compatibility using your full model and serial number. In stock and ready to ship — order today 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 C4850C50ZN055500 — Ships Today?
Yes. This is the factory-specified OEM transformer for the Carrier C4850C50ZN055500 — 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 C4850C50ZN055500 — 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.
Home Shop Search Account Cart
Fitment Guaranteed
MR
Mike Rivera
HVAC Parts Specialist — Online