What are the specs for this Transformer?

The correct replacement for Carrier model PY3PPA042090NA 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 PY3PPA042090NA.

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 Control Transformer 40VA 208/240V–24V for PY3PPA042090NA

Name: OEM Carrier Control Transformer 40VA 208/240V–24V for PY3PPA042090NA
Brand: Carrier
SKU: CARRIE-PY3PPA042090NA-TRANSFORMER-HT01BD209
Price: 47.25 USD
Availability: InStock

SKU: CARRIE-PY3PPA042090NA-TRANSFORMER-HT01BD209 Brand: Carrier

✓ Guaranteed to fit PY3PPA042090NA — or your money back. Terms

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OEM Carrier Control Transformer 40VA 208/240V to 24V for Model PY3PPA042090NA

This is the factory OEM replacement control transformer for the Carrier PY3PPA042090NA packaged unit. The transformer steps down line voltage (208/240V) to the 24V AC signal that powers your thermostat circuit, control board, and all low-voltage safety and switching controls. When this part fails, the entire control circuit goes dark — thermostats become unresponsive, contactors won't energize, and the system will not start. A failed transformer is one of the most common causes of a completely non-functional HVAC unit and is one of the first components a technician should check during a no-call diagnostic.

Specs: OEM Part # HT01BD209 | Input: 208/240V | Output: 24V | Power Rating: 40VA | Frequency: 50/60 Hz | Factory-matched to Carrier PY3PPA042090NA
OEM vs Generic: OEM transformers are wound to exact factory VA tolerances, protecting sensitive control boards from undervoltage brown-outs. Generic transformers often run at looser tolerances, risking nuisance tripping of the low-voltage fuse or premature board failure.
Install Difficulty: 2/5 — Shut off all power at the disconnect and breaker before proceeding. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Photograph existing wiring before disconnecting. Verify primary tap selection matches your supply voltage (208V or 240V) before energizing.
Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse — order by 3 PM for same-day dispatch.

Compatibility: Designed for the Carrier PY3PPA042090NA packaged unit. Always verify your unit's data plate voltage and VA rating before ordering. Not sure if this is the right part? Our HVAC parts specialists verify fitment before you buy — contact us today and we'll confirm compatibility fast.

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

OEM Carrier Control Transformer ...

$47.25

Frequently Asked Questions

Does this Transformer fit my Carrier PY3PPA042090NA?

Yes. This is the factory-specified OEM transformer for the Carrier PY3PPA042090NA. 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 PY3PPA042090NA?

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 Control Transformer 40VA 208/240V–24V for PY3PPA042090NA

OEM Carrier Control Transformer 40VA 208/240V to 24V for Model PY3PPA042090NA

Shipping Information

Return Policy

Frequently Asked Questions