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OEM Carrier Transformer 40VA 120V-24V for FC4DNB042000AAAA
Carrier

OEM Carrier Transformer 40VA 120V-24V for FC4DNB042000AAAA

SKU: CARRIE-FC4DNB042000AAAA-TRANSFORMER-HT01CN241 Brand: Carrier

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Texas CMBL #19328542014
SAM.gov Registered
Govt POs Accepted

OEM Carrier Transformer 40VA 120V to 24V for Model FC4DNB042000AAAA

This OEM step-down transformer (part number HT01CN241) is the factory-specified replacement for the Carrier FC4DNB042000AAAA fan coil unit. The transformer converts 120V line voltage down to the 24V AC signal that powers the entire control circuit — including the thermostat, contactor coil, and integrated control board. When this component fails, nothing in the system responds: the thermostat goes dark, the blower won't energize, and the unit sits completely dead despite line voltage being present at the unit.

  • Specs: 40VA capacity | 120V primary input | 24V secondary output | Direct OEM replacement for part number HT01CN241 | Factory-matched impedance and insulation class
  • OEM vs Generic: This factory OEM transformer is wound to exact VA and voltage tolerances required by the FC4DNB042000AAAA control circuit. Undersized or off-tolerance generic transformers can overheat, trip thermal cutoffs prematurely, or deliver insufficient current to hold contactor coils closed — causing intermittent lockouts that are difficult to diagnose.
  • Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before starting. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Photograph all wiring connections before removing the old transformer. 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 HVAC-dedicated warehouse when ordered before 3 PM local time.

Compatibility: Designed specifically for the Carrier FC4DNB042000AAAA fan coil unit. Always confirm the OEM part number HT01CN241 against your unit's wiring diagram or data plate before ordering. Our parts specialists are available to verify fitment — contact us before you order if you have any questions. In stock and ready to ship 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 FC4DNB042000AAAA?
Yes. This is the factory-specified OEM transformer for the Carrier FC4DNB042000AAAA. 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 FC4DNB042000AAAA?
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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