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OEM Carrier Transformer 40VA 120V to 24V for C4850C50Z2035500 | National HVAC Parts
Carrier

OEM Carrier Transformer 40VA 120V to 24V for C4850C50Z2035500 | National HVAC Parts

SKU: CARRIE-C4850C50Z2035500-TRANSFORMER-HT01BD236 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier 40VA Control Transformer HT01BD236 for Model C4850C50Z2035500

This OEM control transformer (part number HT01BD236) is the factory-specified replacement for the Carrier C4850C50Z2035500 packaged unit. The transformer steps down line voltage from 120V to 24V to power the entire low-voltage control circuit — including the thermostat, contactor coil, and control board. When this component fails, the entire control system goes dark: the thermostat displays nothing, no calls for heating or cooling are processed, and the unit will not respond to any commands. It is often the first component to inspect when a unit appears completely unresponsive.

  • Specs: 40VA rated | 120V primary / 24V secondary | OEM part number HT01BD236 | Factory-matched output for stable control voltage
  • OEM vs Generic: OEM transformers are wound to exact VA and voltage specifications required by the Carrier control board. Undersized or off-tolerance generic transformers can cause nuisance trips, board damage, or repeated blown fuses in the control circuit.
  • Install Difficulty: 2/5 — Shut off all power to the unit before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to verify 24V output after install). Label or photograph all low-voltage wiring connections before removal.
  • Warranty: 1-year OEM factory warranty. Orders placed before cutoff ship same business day from our warehouse.

Compatibility: Designed for use in the Carrier C4850C50Z2035500 packaged unit. Confirm your existing transformer's VA rating and primary/secondary voltages on the data plate before ordering. Our parts specialists are available to verify fitment — contact us before you buy 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 C4850C50Z2035500 | National HVAC Parts?
Yes. This is the factory-specified OEM transformer for the Carrier C4850C50Z2035500 | 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 C4850C50Z2035500 | 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.
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Mike Rivera
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