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OEM Carrier Transformer 208/230V–24V 40VA for PF4MNB031T00AAAA
Carrier

OEM Carrier Transformer 208/230V–24V 40VA for PF4MNB031T00AAAA

SKU: CARRIE-PF4MNB031T00AAAA-TRANSFORMER-HT01CN241 Brand: Carrier
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Texas CMBL #19328542014
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OEM Carrier Control Transformer 208/230V–24V 40VA for Model PF4MNB031T00AAAA

This is the genuine OEM replacement control transformer for the Carrier PF4MNB031T00AAAA fan coil and air handler unit. The transformer steps down line voltage (208/230V primary) to the 24V AC signal that powers your thermostat, control board, relays, and zone valves. When this transformer fails, the entire control circuit goes dead — your thermostat goes blank, the system stops responding to calls for heating or cooling, and no error codes are generated because the board itself has no power. Replacing it with the correct OEM unit restores full system operation immediately.

  • Specs: 208/230V primary | 24V secondary | 40VA rated | OEM Part # HT01CN241 | Direct factory drop-in replacement
  • OEM vs Generic: This is a genuine Carrier Factory Authorized Part built to exact output voltage and VA tolerances. Undersized or off-spec aftermarket transformers can starve the control board under load, causing erratic lockouts and premature board failure.
  • Install difficulty: 2/5 — Shut off power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter (to confirm 24V output after install), wire nuts or spade connectors. Label all low-voltage wires before disconnecting. Verify 24VAC output with a meter before closing the unit.
  • Warranty: 1-year OEM manufacturer warranty. In-stock units ship same business day from our warehouse when ordered by cutoff time.

Compatibility: Designed as the factory-specified replacement for the Carrier PF4MNB031T00AAAA fan coil/air handler. Confirm your existing transformer's primary voltage (208V or 230V) and VA rating on the data plate before ordering. Need fitment verification? Our HVAC parts specialists confirm compatibility before you buy — no guesswork required.

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 PF4MNB031T00AAAA?
Yes. This is the factory-specified OEM transformer for the Carrier PF4MNB031T00AAAA. 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 PF4MNB031T00AAAA?
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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