What are the specs for this Transformer?

The correct replacement for Carrier model C4850C50ZG055500 | National HVAC Parts is this exact part. It is the factory-specified replacement with exact OEM specifications. Using a part with different specifications can cause equipment damage or void your warranty. You can verify this by checking the data plate on your Carrier equipment which lists the model number C4850C50ZG055500 | National HVAC Parts.

Is this transformer compatible with Bryant or Payne systems too?

Many Carrier parts are cross-compatible with Bryant and Payne systems since all three brands are manufactured by Carrier Global Corporation. The same physical part is often used across multiple brand labels with different model numbers. To verify cross-compatibility, check your Bryant or Payne equipment service manual for cross-compatible part numbers, or contact info@nationalhvacparts.com with your model number for confirmation.

Carrier

OEM Carrier Transformer 40VA 120V to 24V for C4850C50ZG055500 | National HVAC Parts

Name: OEM Carrier Transformer 40VA 120V to 24V for C4850C50ZG055500 | National HVAC Parts
Brand: Carrier
SKU: CARRIE-C4850C50ZG055500-TRANSFORMER-HT01BD236
Price: 47.25 USD
Availability: InStock

SKU: CARRIE-C4850C50ZG055500-TRANSFORMER-HT01BD236 Brand: Carrier

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OEM Carrier Control Circuit Transformer 40VA for Model C4850C50ZG055500

This OEM Carrier transformer (part# HT01BD236) is the factory-specified replacement for the Carrier C4850C50ZG055500 packaged unit. The transformer steps down 120V line voltage to the 24V signal voltage that powers your thermostat, control board, and all low-voltage safety circuits. When this component fails, the entire control circuit goes dark — your thermostat will appear dead, the system won't respond to any inputs, and no heating or cooling will occur. It is often the first component to inspect when nothing works at all.

Specs: 40VA rating | Primary: 120V | Secondary: 24V | Factory-matched OEM part number HT01BD236 | Built-in circuit protection fuse on most configurations
OEM vs Generic: OEM transformers are wound and insulated to Carrier's exact VA and impedance specifications. Undersized or off-spec generic units can overheat, blow the secondary fuse repeatedly, or fail to sustain voltage under full control-circuit load — causing nuisance lockouts and premature board damage.
Install difficulty: 2/5 — Disconnect power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter (to confirm 24V output after install). Label or photograph all low-voltage wiring before disconnecting terminals.
Warranty: 1-year OEM factory warranty. Orders placed before cutoff ship same business day from our warehouse.

Compatibility: Engineered specifically for the Carrier C4850C50ZG055500 packaged unit. Confirm your existing transformer's VA rating and primary/secondary voltages on the unit's data plate or wiring diagram before ordering. Our fitment team is available to verify compatibility — don't guess on a control-circuit component. Order today and your part ships same business day.

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

OEM Carrier Transformer 40VA 120...

$47.25

Frequently Asked Questions

Does this Transformer fit my Carrier C4850C50ZG055500 | National HVAC Parts?

Yes. This is the factory-specified OEM transformer for the Carrier C4850C50ZG055500 | National HVAC Parts. 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 C4850C50ZG055500 | National HVAC Parts?

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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OEM Carrier Transformer 40VA 120V to 24V for C4850C50ZG055500 | National HVAC Parts

OEM Carrier Control Circuit Transformer 40VA for Model C4850C50ZG055500

Shipping Information

Return Policy

Frequently Asked Questions