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OEM Carrier Transformer 40VA 120V/24V for FV4CNF003T00ABAA
Carrier

OEM Carrier Transformer 40VA 120V/24V for FV4CNF003T00ABAA

SKU: CARRIE-FV4CNF003T00ABAA-TRANSFORMER-HT01CN236 Brand: Carrier

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Texas CMBL #19328542014
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Govt POs Accepted

OEM Carrier Transformer 40VA 120V/24V for Model FV4CNF003T00ABAA

This OEM replacement transformer (part number HT01CN236) is the factory-specified control circuit transformer for the Carrier FV4CNF003T00ABAA fan coil air handler. The transformer steps down line voltage from 120V AC to the 24V AC signal that powers your thermostat, control board, and all low-voltage control components. When this transformer fails, the entire control circuit goes dead — your thermostat will display nothing or fail to communicate, and the system will not respond to any heating or cooling calls. A failed transformer is often indicated by a blown 3-amp fuse on the control board, frequently caused by a short in the low-voltage wiring.

  • Specs: 40VA rating | 120V primary / 24V secondary | OEM part number HT01CN236 | Factory-matched output for stable low-voltage control circuit operation
  • OEM vs Generic: This factory OEM transformer is wound to exact VA and voltage tolerances required by Carrier. Undersized or off-tolerance generic transformers can cause nuisance tripped fuses, erratic thermostat behavior, and premature control board failure.
  • Install Difficulty: 2/5 — Disconnect power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Always verify input/output voltage with a multimeter after installation before restoring power. Photograph all wiring connections prior to removal.
  • Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Designed as a direct OEM replacement for the Carrier FV4CNF003T00ABAA fan coil air handler. Verify your existing transformer's VA rating and voltage specifications on the unit's data plate or wiring diagram before ordering. Our parts specialists are available to confirm fitment — order with confidence and get your system back online 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 FV4CNF003T00ABAA?
Yes. This is the factory-specified OEM transformer for the Carrier FV4CNF003T00ABAA. 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 FV4CNF003T00ABAA?
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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