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OEM Carrier Transformer 40VA 120V/24V for FX4ANF042000ABAA
Carrier

OEM Carrier Transformer 40VA 120V/24V for FX4ANF042000ABAA

SKU: CARRIE-FX4ANF042000ABAA-TRANSFORMER-HT01CN236 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier 40VA Control Transformer HT01CN236 for Model FX4ANF042000ABAA

This OEM replacement transformer (part number HT01CN236) is the factory-specified control transformer for the Carrier FX4ANF042000ABAA fan coil air handler. Its job is to step down 120V line voltage to the 24V signal voltage that powers your thermostat, control board, and all low-voltage switching circuits. When this transformer fails, the entire control circuit goes dead — the thermostat displays nothing, the system will not respond to any calls for heating or cooling, and you may measure zero volts at the 24V secondary terminals. This is one of the most overlooked causes of a completely unresponsive HVAC system.

  • Specs: 40VA rated | 120V primary / 24V secondary | Class 2 transformer | Hardwire mount | OEM part number HT01CN236 | Factory-matched output for stable low-voltage control circuits
  • OEM vs Generic: This factory OEM transformer is wound to exact VA and voltage tolerances for the FX4ANF042000ABAA. Generic transformers frequently run underrated VA, causing thermal cutout trips and erratic low-voltage behavior — particularly under simultaneous thermostat and zone board loads.
  • Install difficulty: 2/5 — Disconnect all power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Label all low-voltage wires prior to removal. Verify 24V output with a multimeter after installation before restoring full system power.
  • Warranty: 1-year OEM factory warranty against defects. Ships same business day from our warehouse stock.

Compatibility: Engineered specifically for the Carrier FX4ANF042000ABAA fan coil air handler. Confirm your existing transformer's VA rating and primary/secondary voltages on the unit's data plate before ordering. Our parts specialists are available to verify fitment — order with confidence and get back up and running 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 $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 FX4ANF042000ABAA?
Yes. This is the factory-specified OEM transformer for the Carrier FX4ANF042000ABAA. 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 FX4ANF042000ABAA?
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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