{"product_id":"carrier-pf4mnb043t00abaa-transformer-h3hwwy","title":"OEM Carrier Control Transformer 40VA 208\/230V — PF4MNB043T00ABAA","description":"\u003ch1\u003eOEM Carrier Control Transformer 40VA 208\/230V→24V for Model PF4MNB043T00ABAA\u003c\/h1\u003e\u003cp\u003eThis OEM control transformer (part number \u003cstrong\u003eHT01CN241\u003c\/strong\u003e) is the factory-specified replacement for the \u003cstrong\u003eCarrier PF4MNB043T00ABAA\u003c\/strong\u003e air handler. The transformer steps down line voltage (208\/230V primary) to the 24V AC signal that powers your thermostat, control board, and every relay in the system. When it fails, the entire control circuit goes dead — the thermostat goes blank, the system will not respond to any call for heating or cooling, and fuses may blow repeatedly if a shorted secondary winding is the root cause.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 208\/230V Primary | 24V Secondary | 40VA rated | OEM part number HT01CN241 | Factory-matched to Carrier PF4MNB043T00ABAA wiring harness and mounting footprint\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM Carrier transformers are wound to exact VA and voltage tolerances. Under-rated or off-spec generic transformers overheat, trip internal thermal cutoffs prematurely, and can damage control boards through voltage sag — especially under heavy relay-switching loads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect all power at the breaker and verify with a multimeter before touching any terminals. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Always label the 24V secondary wires before disconnecting. The swap is typically 20–30 minutes for an experienced DIYer.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM manufacturer warranty. In-stock units ship same business day from our warehouse when ordered before cut-off.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Engineered as a direct OEM replacement for the Carrier \u003cstrong\u003ePF4MNB043T00ABAA\u003c\/strong\u003e air handler. Verify your unit's data plate shows a 208\/230V primary and 24V\/40VA control circuit before ordering. Not sure it fits? Contact our parts team — we verify fitment before you buy. \u003cstrong\u003eOrder now and ship today.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62643259965811,"sku":"CARRIE-PF4MNB043T00ABAA-TRANSFORMER-HT01CN241","price":108.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62643259998579,"sku":"CARRIE-PF4MNB043T00ABAA-TRANSFORMER-HT01CN241-GEN","price":95.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-HT01CN241_45946fc4-953f-4fb9-a75b-58dfe850b9b4.jpg?v=1775025459","url":"https:\/\/nationalhvacparts.com\/products\/carrier-pf4mnb043t00abaa-transformer-h3hwwy","provider":"National HVAC Parts","version":"1.0","type":"link"}