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OEM Carrier 40VA 120V to 24V Transformer for C4850C50ZG030500 | National HVAC Parts
Carrier

OEM Carrier 40VA 120V to 24V Transformer for C4850C50ZG030500 | National HVAC Parts

SKU: CARRIE-C4850C50ZG030500-TRANSFORMER-HT01BD236 Brand: Carrier
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Texas CMBL #19328542014
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OEM Carrier Transformer 40VA 120V to 24V for Model C4850C50ZG030500

This is the OEM factory-replacement control circuit transformer for the Carrier C4850C50ZG030500 packaged unit, sold under OEM part number HT01BD236. The transformer steps down 120V line voltage to 24V AC to power the low-voltage control circuit — including the thermostat, contactor coil, and control board. When this transformer fails, the entire control system goes dark: the thermostat shows no response, the unit won't start, and you may measure 0V at the secondary terminals despite line voltage being present. A failed transformer is often caused by a shorted control wire or failed component elsewhere in the 24V circuit, so always inspect for downstream faults before replacing.

  • Specs: 40VA rated | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01BD236 | Replaces factory-installed transformer on Carrier C4850C50ZG030500
  • OEM vs Generic: This OEM transformer is wound to exact factory VA and voltage tolerances. Undersized or off-brand transformers can overheat and trip the built-in thermal fuse, leaving you chasing a second failure within weeks.
  • Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire stripper. Label and photograph all wiring connections before removing the old unit. Check secondary voltage (24V) with power restored before reassembling the panel.
  • Warranty: 1-year OEM factory warranty. Orders placed by 3PM ship same business day from our warehouse.

Compatibility: Designed for the Carrier C4850C50ZG030500 packaged unit. Confirm your existing transformer's VA rating and primary/secondary voltages on the unit's data plate or wiring diagram before ordering. Need help confirming fitment? Our HVAC parts specialists verify compatibility before every order — call or chat today.

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 $99
  • 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 C4850C50ZG030500 | National HVAC Parts?
Yes. This is the factory-specified OEM transformer for the Carrier C4850C50ZG030500 | 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 C4850C50ZG030500 | 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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