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OEM Carrier Transformer 40VA 120V to 24V for C48A202551 — Ships Today
Carrier

OEM Carrier Transformer 40VA 120V to 24V for C48A202551 — Ships Today

SKU: CARRIE-C48A202551-TRANSFORMER-HT01BD236 Brand: Carrier
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Texas CMBL #19328542014
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OEM Carrier 40VA Control Transformer for Model C48A202551

This OEM Carrier transformer (part number HT01BD236) is the factory-specified replacement for the C48A202551 packaged unit. The transformer steps down 120V line voltage to the 24V signal used by your thermostat, control board, and safety circuits. When the transformer fails, the entire control circuit goes dead — the thermostat goes blank, the system won't respond to any calls for heating or cooling, and no components will energize. It is one of the most overlooked yet critical components in the unit.

  • Specs: 40VA rated | Primary: 120V | Secondary: 24V | OEM part number HT01BD236 | Factory-matched to Carrier C48A202551 electrical specifications
  • OEM vs Generic: This OEM transformer is wound to Carrier's exact VA rating and insulation class. Generic transformers often run under-rated VA, causing overheating and premature failure — especially in systems with multiple 24V accessories such as zone dampers or humidifiers.
  • Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Verify primary and secondary voltages after installation before restoring full power. Always label or photograph existing wiring before disconnecting terminals.
  • Warranty: 1-year OEM factory warranty. Orders placed before cutoff ship the same business day from our stocked warehouse.

Compatibility: Designed specifically for the Carrier C48A202551 packaged unit. Confirm your unit's data plate shows matching primary voltage (120V) before ordering. If you are unsure of fitment, our HVAC parts specialists can verify compatibility before you purchase. Order today and get back to comfort fast — in stock and ships 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 C48A202551 — Ships Today?
Yes. This is the factory-specified OEM transformer for the Carrier C48A202551 — Ships Today. 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 C48A202551 — Ships Today?
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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