Same-day shipping on orders before 3PM CST · 15,000+ OEM Parts In Stock · Carrier · Bryant · ICP · Heil · Tempstar
Track Order | 1-800-NHP-HVAC | Trade Accounts

Menu

Home Shop All Account Cart
Home / OEM Carrier Transformer for Fan Coil ...
OEM Carrier Transformer for Fan Coil Model FX4CNB042000AAAA
Carrier

OEM Carrier Transformer for Fan Coil Model FX4CNB042000AAAA

SKU: carrier-transformer-fx4cnb042000aaaa Brand: Carrier
$49.95

Order before 3PM CST — ships same day.
Standard delivery 2-5 business days. Express options at checkout.

OEM Guaranteed

Same-Day Ship

30-Day Returns

Secure Checkout

OEM Carrier Transformer for Fan Coil Model FX4CNB042000AAAA

Restore reliable control power to your Carrier FX4CNB042000AAAA fan coil with this genuine OEM transformer. The transformer converts incoming line voltage to the 24-volt power that drives the thermostat, control board, and contactor. A burned-out or buzzing transformer often shows up as a blank thermostat, a system that won't start, or breakers and fuses that keep tripping. This factory replacement matches the original VA rating and primary/secondary voltages, so it drops in without guesswork and runs cool under normal load. Engineered to Carrier specs, it delivers steady low-voltage output and shields sensitive electronics from spikes. The install is a moderate task for a handy homeowner or pro: kill the power, note the wiring, swap leads to the new transformer, mount it, and restore power—typically 20 to 30 minutes. Choosing the OEM part guarantees correct fit and dependable performance over universal alternatives. We keep this part in stock and ship same-day on orders placed before 3PM CST.

Compatibility

This part is compatible with Carrier model FX4CNB042000AAAA.

Shipping

Same-day shipping before 3 PM CST. 30-day returns on uninstalled parts.

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 support@nationalhvacparts.com to initiate a return
  • Refunds processed within 5-7 business days

Frequently Asked Questions

Does this Transformer fit my Carrier Fan Coil Model FX4CNB042000AAAA?
Yes. This is the factory-specified OEM transformer for the Carrier Fan Coil Model FX4CNB042000AAAA. 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 Fan Coil Model FX4CNB042000AAAA?
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.
Home Shop Search Account Cart