{"product_id":"carrier-ph13nb042000aaaa-transformer-h4oyjb","title":"OEM Carrier Transformer 40VA 120V–24V for PH13NB042000AAAA","description":"\u003ch1\u003eOEM Carrier Control Transformer 40VA 120V–24V for Model PH13NB042000AAAA\u003c\/h1\u003e\u003cp\u003eThis OEM Carrier transformer (part number \u003cstrong\u003eHT01AW229\u003c\/strong\u003e) is the factory-specified replacement for the \u003cstrong\u003eCarrier PH13NB042000AAAA\u003c\/strong\u003e heat pump system. The transformer steps down line voltage (120V) to low-voltage control circuit power (24V AC), energizing the thermostat, contactor coil, and all control board logic. When it fails, the entire control circuit goes dead — the thermostat displays nothing, the system won't respond to any call for heating or cooling, and you may find a blown 3A fuse on the control board as a secondary symptom.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | Primary: 120V AC | Secondary: 24V AC | Factory-matched OEM construction | Replaces OEM part number HT01AW229\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This OEM unit meets Carrier's exact VA rating and insulation class. Undersized or off-tolerance generic transformers can overheat, trip thermal cutoffs prematurely, or fail to hold 24V under load — causing intermittent lockouts that are difficult to diagnose.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect power at the breaker and verify zero voltage with a multimeter before touching any wiring. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Photograph all wiring before disconnecting. Replace the 3A control fuse if blown during the same service call.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty against defects. In-stock and ships same business day from our warehouse.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Designed as a direct OEM replacement for the Carrier \u003cstrong\u003ePH13NB042000AAAA\u003c\/strong\u003e heat pump. Verify primary voltage (120V) and secondary voltage (24V) against your unit's data plate before ordering. Our team is available to confirm fitment — reach out before you buy if you have any questions.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62641915986291,"sku":"CARRIE-PH13NB042000AAAA-TRANSFORMER-HT01AW229","price":34.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62641916019059,"sku":"CARRIE-PH13NB042000AAAA-TRANSFORMER-HT01AW229-GEN","price":30.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-HT01AW229_b66622af-690b-46c4-98a6-3f77eb3ffd9e.jpg?v=1775041401","url":"https:\/\/nationalhvacparts.com\/products\/carrier-ph13nb042000aaaa-transformer-h4oyjb","provider":"National HVAC Parts","version":"1.0","type":"link"}