{"product_id":"carrier-ph3znb030000aa-transformer-h30291","title":"OEM Carrier Transformer 40VA 208\/240V–24V for PH3ZNB030000AA","description":"\u003ch1\u003eOEM Carrier Control Transformer 40VA 208\/240V to 24V — Model PH3ZNB030000AA\u003c\/h1\u003e\u003cp\u003eThe Carrier \u003cstrong\u003eHT01BD209\u003c\/strong\u003e is the factory-specified control transformer for the \u003cstrong\u003eCarrier PH3ZNB030000AA\u003c\/strong\u003e packaged HVAC unit. This transformer steps down the line-voltage power supply (208\/240V) to the 24V AC signal that energizes your thermostat, control board, contactor coils, and all low-voltage safety circuits. When the transformer fails, the entire control circuit goes dark — the thermostat goes blank, the system refuses to respond to any call for heating or cooling, and no diagnostic fault codes will appear. Replacing this transformer is often the first step in restoring a completely unresponsive system.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 208\/240V primary input | 24V secondary output | 40VA power rating | 50\/60Hz | Replaces OEM part HT01CN232\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This is the genuine Carrier OEM transformer, wound to exact factory VA and voltage tolerances. Undersized or off-tolerance aftermarket transformers can overheat, trip thermal cutoffs, or deliver unstable 24V that causes nuisance lockouts and board damage.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Turn off power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph all wire connections before removal. Verify 24V output at secondary terminals after installation before reconnecting the load.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty. In stock and ships same business day from our warehouse.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Direct OEM replacement for Carrier model \u003cstrong\u003ePH3ZNB030000AA\u003c\/strong\u003e. Also cross-references to superseded Carrier part HT01CN232. Verify your unit's data plate voltage before ordering to confirm 208\/240V primary input. Need help confirming fitment? Our HVAC parts specialists are available to verify compatibility before you order — same-day shipping available on all in-stock orders.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62641340383603,"sku":"CARRIE-PH3ZNB030000AA-TRANSFORMER-HT01BD209","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62641340416371,"sku":"CARRIE-PH3ZNB030000AA-TRANSFORMER-HT01BD209-GEN","price":18.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-HT01BD209_93c40bec-71af-404d-a00e-448c79013ad3.jpg?v=1782942235","url":"https:\/\/nationalhvacparts.com\/products\/carrier-ph3znb030000aa-transformer-h30291","provider":"National HVAC Parts","version":"1.0","type":"link"}