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OEM Carrier Transformer 40VA 120V-24V for FC4DNF018000AAAA
Carrier

OEM Carrier Transformer 40VA 120V-24V for FC4DNF018000AAAA

SKU: CARRIE-FC4DNF018000AAAA-TRANSFORMER-HT01CN241 Brand: Carrier

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Texas CMBL #19328542014
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OEM Carrier Transformer 40VA 120V to 24V for Model FC4DNF018000AAAA

This is the factory OEM replacement transformer (part number HT01CN241) for the Carrier FC4DNF018000AAAA fan coil unit. The transformer steps down line voltage from 120V to the 24V AC signal required by the control circuit, thermostat, and all low-voltage components. When the transformer fails, the entire control system goes dark — the thermostat displays nothing, the unit won't respond to any call for heating or cooling, and no low-voltage components operate. A failed transformer is often mistaken for a bad control board, so always confirm 24V output at the secondary before replacing any other components.

  • Specs: 40VA rating | 120V primary input | 24V secondary output | Direct OEM replacement for part number HT01CN241 | Factory-matched impedance and thermal protection
  • OEM vs Generic: OEM transformers are wound to exact VA and voltage specifications for the Carrier FC4DNF018000AAAA. Generic substitutes may lack internal thermal fusing, putting your control board and low-voltage wiring at risk during a fault condition.
  • Install difficulty: 2/5 — Shut off all power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or terminal connectors. Test for 24V output at secondary terminals after installation before restoring full system power.
  • Warranty: 1-year OEM factory warranty against defects in materials and workmanship. Ships same business day from our warehouse stock.

Compatibility: Designed specifically for the Carrier FC4DNF018000AAAA fan coil unit. Confirm primary voltage (120V) and VA rating on your unit's data plate before ordering. If you are unsure of fitment, our HVAC parts specialists can verify compatibility before you purchase — same-day shipping available on all in-stock orders placed before 3 PM local time.

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 FC4DNF018000AAAA?
Yes. This is the factory-specified OEM transformer for the Carrier FC4DNF018000AAAA. 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 FC4DNF018000AAAA?
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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