{"product_id":"carrier-ph3gpaa42000aa-transformer-h3025m","title":"OEM Carrier Transformer 75VA 208\/240\/480V-24V for PH3GPAA42000AA","description":"\u003ch1\u003eOEM Carrier Control Transformer 75VA 208\/240\/480V to 24VAC — HT01BD242 for Model PH3GPAA42000AA\u003c\/h1\u003e\u003cp\u003eThis OEM control transformer is the factory-specified replacement for the \u003cstrong\u003eCarrier PH3GPAA42000AA\u003c\/strong\u003e packaged heat pump unit. The transformer steps down high-voltage line power (208\/240\/480V primary) to the 24VAC signal required by the low-voltage control circuit — powering your thermostat, contactor coil, and all safety controls. When this transformer fails, the entire control circuit goes dead: the thermostat goes blank, the system will not respond to any call for heating or cooling, and no safety devices can operate. A failed transformer is often misdiagnosed as a thermostat or control board issue, making correct identification critical before replacing more expensive components.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 75VA power rating | Primary voltage: 208\/240\/480VAC | Secondary voltage: 24VAC | Frequency: 50\/60Hz | Foot-mount configuration | OEM part number HT01BD242\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This is the genuine Carrier OEM transformer built to exact factory VA and voltage tolerances. Generic transformers often run under-rated VA capacities, causing premature thermal cutout trips or undervoltage to the control board — accelerating downstream component failures.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 3\/5\u003c\/strong\u003e — Requires disconnecting line-voltage wiring. Always shut off all power at the disconnect and breaker before servicing. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to verify 24VAC output after install), and wire labels. Check for a shorted 24V circuit (blown fuse or tripped limit) before installing the new transformer — installing into an unresolved short will immediately damage the replacement.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty. In-stock units ship same business day from our warehouse when ordered before cutoff.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Engineered as the direct OEM replacement for \u003cstrong\u003eCarrier model PH3GPAA42000AA\u003c\/strong\u003e packaged heat pump units. This transformer is also cross-referenced across Carrier, Bryant, Payne, and ICP family equipment sharing the HT01BD242 specification. Always verify primary voltage matches your unit's supply voltage on the data plate before ordering. Have a question about fitment? Our HVAC parts specialists verify compatibility before you buy — contact us today and get your system back online fast.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62641351557491,"sku":"CARRIE-PH3GPAA42000AA-TRANSFORMER-HT01BD242","price":70.2,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62641351590259,"sku":"CARRIE-PH3GPAA42000AA-TRANSFORMER-HT01BD242-GEN","price":23.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-HT01BD242_08d10667-d739-49e5-b838-0637451a119c.jpg?v=1782943209","url":"https:\/\/nationalhvacparts.com\/products\/carrier-ph3gpaa42000aa-transformer-h3025m","provider":"National HVAC Parts","version":"1.0","type":"link"}