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 C4850C50AK04061 | National HVAC Parts
Carrier

OEM Carrier Transformer 40VA 120V to 24V for C4850C50AK04061 | National HVAC Parts

SKU: CARRIE-C4850C50AK04061-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 40VA Control Transformer for Model C4850C50AK04061

This OEM replacement control transformer is the factory-specified unit for the Carrier C4850C50AK04061 packaged unit. The transformer steps down line voltage (120V) to the 24V signal used by your thermostat, control board, contactor coil, and all low-voltage safety circuits. When this transformer fails, the entire control circuit goes dark — the thermostat becomes unresponsive, the system will not call for heating or cooling, and no safety safeties can trip or reset. It is often the first component to check when a system is completely non-responsive but line voltage is confirmed present.

  • Specs: 40VA rated | Primary: 120V | Secondary: 24V | OEM part number HT01BD236 | Factory-matched impedance and thermal protection
  • OEM vs Generic: OEM transformers are wound to exact VA and impedance specs for this unit. Undersized or off-tolerance generic transformers can overheat, trip thermal cutoffs prematurely, or fail to sustain voltage under load — leaving you with an intermittent fault that is difficult to diagnose.
  • Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before proceeding. Tools needed: flathead and Phillips screwdrivers, wire nuts or terminal connectors, multimeter to confirm 24V output after installation. Label or photograph all wiring before disconnecting.
  • Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier C4850C50AK04061 packaged unit. Verify OEM part number HT01BD236 against your unit's data plate or existing transformer label before ordering. If you are unsure of fitment, our parts team can confirm compatibility before you place your order — same-day shipping on all in-stock items.

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 C4850C50AK04061 | National HVAC Parts?
Yes. This is the factory-specified OEM transformer for the Carrier C4850C50AK04061 | National HVAC Parts. 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 C4850C50AK04061 | National HVAC Parts?
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