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OEM Carrier Control Transformer 40VA 208/230V–24V — PF4MNB031L00ABAA
Carrier

OEM Carrier Control Transformer 40VA 208/230V–24V — PF4MNB031L00ABAA

SKU: CARRIE-PF4MNB031L00ABAA-TRANSFORMER-HT01CN241 Brand: Carrier
✓ Guaranteed to fit PF4MNB031L00ABAA — or your money back. Terms

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Texas CMBL #19328542014
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OEM Carrier Control Transformer 40VA 208/230V to 24V for Model PF4MNB031L00ABAA

This OEM Carrier control transformer (part #HT01CN241) is the factory-specified replacement for the Carrier PF4MNB031L00ABAA fan coil unit. The transformer steps down the 208/230V line voltage to 24V AC, powering the entire low-voltage control circuit — including the thermostat, contactors, and control board. When this transformer fails, the system loses all 24V control signal: the thermostat goes dark, no calls for heating or cooling are processed, and the unit is completely unresponsive despite line power being present.

  • Specs: 208/230V Primary | 24V Secondary | 40VA Capacity | OEM Part #HT01CN241 | Factory-matched to Carrier electrical tolerances
  • OEM vs Generic: This OEM transformer is wound and rated to exact Carrier factory specifications, ensuring the correct VA headroom for all control loads on the PF4MNB031L00ABAA. Undersized or off-spec generic transformers frequently overheat, trip thermal protection, or fail prematurely under combined relay and board loads.
  • Install difficulty: 2/5 — Always disconnect power at the breaker before servicing. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to verify 24V output after install). Photograph all low-voltage wiring before disconnecting. Replacement is straightforward — the transformer mounts to a chassis bracket with two screws and uses push-on or screw terminals.
  • Warranty: 1-year OEM manufacturer warranty. In stock and ships same business day from our warehouse when ordered before cutoff.

Compatibility: Direct OEM replacement for Carrier model PF4MNB031L00ABAA fan coil units. Verify primary voltage tap on your unit's data plate (208V or 230V) before ordering — both taps are supported by this transformer. Questions about fitment? Our HVAC parts specialists verify compatibility before you order — contact us 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 $99
  • 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 OEM Carrier Control Transformer 40VA 208/230V–24V — PF4MNB031L00ABAA?
Yes. This is the factory-specified OEM transformer for the Carrier OEM Carrier Control Transformer 40VA 208/230V–24V — PF4MNB031L00ABAA. 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 OEM Carrier Control Transformer 40VA 208/230V–24V — PF4MNB031L00ABAA?
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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