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OEM Carrier Transformer 120V–24V 40VA for UPFLOW100U4219A
Carrier

OEM Carrier Transformer 120V–24V 40VA for UPFLOW100U4219A

SKU: CARRIE-UPFLOW100U4219A-TRANSFORMER-HT01CN001 Brand: Carrier
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OEM Carrier Furnace Transformer 120V to 24V 40VA — Model UPFLOW100U4219A

This is the genuine OEM Carrier transformer (part number HT01CN001), factory-specified for the UPFLOW100U4219A upflow furnace. The transformer steps down 120V line voltage to a safe 24V (with 12V secondary tap) to power all low-voltage control circuits — including the thermostat, control board relay coils, and zone valves. At 40VA, it delivers sufficient capacity for multi-stage systems. When this transformer fails, the entire control circuit loses power: the thermostat goes blank, the furnace will not respond to any call for heat, and diagnostics cannot run. Common causes of failure include voltage surges, short circuits in low-voltage wiring, and age-related winding breakdown.

  • Specs: 120V primary | 24V / 12V secondary | 40VA rated | Factory-matched Carrier OEM replacement | Replaces legacy part numbers HT01BJ115, 19EA41612, 19EA42612
  • OEM vs Generic: The OEM HT01CN001 is wound to exact Carrier factory tolerances, ensuring stable 24V output under full load. Generic aftermarket transformers may under-deliver on VA capacity, causing nuisance brownouts and premature control board failure.
  • Install Difficulty: 2/5 — Shut off power at the disconnect and breaker before starting. Tools needed: flathead and Phillips screwdrivers, multimeter (to confirm 24VAC output after install), wire stripper/connectors if needed. Label all low-voltage wires before disconnecting. Confirm no short circuits in the 24V wiring loop before energizing, or the new transformer may fail immediately.
  • Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Engineered as a direct OEM replacement for the Carrier UPFLOW100U4219A upflow furnace. Verify part number and voltage rating on your unit's data label before ordering. Our technical team is available to confirm fitment — contact us before you buy if you have any questions. Order today and get same-day shipping on in-stock 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 $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 UPFLOW100U4219A?
Yes. This is the factory-specified OEM transformer for the Carrier UPFLOW100U4219A. 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 UPFLOW100U4219A?
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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