{"product_id":"icp-24v-transformer-for-rgs243hrfa0aaaa-40va-control-power-ships-today","title":"ICP 24V Transformer for RGS243HRFA0AAAA — 40VA Control Power | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\u003cp\u003eThis OEM 24-volt control transformer supplies the low-voltage power that drives the relays, contactor coil, and control logic in the ICP RGS243HRFA0AAAA system. Rated at 40VA with a 24V secondary, it converts incoming line voltage down to the 24VAC required by the unit's DPDT relay (OEM 1183814 \/ T92S11A22-24) and DPST relay (OEM 1178205 \/ T92P7A22-24). When the transformer fails, the entire control circuit goes dead — the thermostat loses power, relays stop pulling in, and the system will not start even though high-voltage power is present. A buzzing transformer, a blown low-voltage fuse, or 0 volts across the secondary terminals are classic signs of a unit at the end of its life.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpec\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOEM Part Numbers\u003c\/td\u003e\n\u003ctd\u003e1183814, 1178205\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType\u003c\/td\u003e\n\u003ctd\u003eControl Transformer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eICP \/ Tempstar \/ Heil\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSecondary Voltage\u003c\/td\u003e\n\u003ctd\u003e24V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRating\u003c\/td\u003e\n\u003ctd\u003e40VA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFit\u003c\/td\u003e\n\u003ctd\u003eOEM Direct Replacement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cp\u003eEngineered as a direct-fit replacement for the ICP\/Tempstar\/Heil RGS243HRFA0AAAA and closely related RGS243 series units. Supplies control voltage to the 24V DPDT and DPST relays used in this platform.\u003c\/p\u003e\u003ch3\u003eInstallation Guide\u003c\/h3\u003e\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eSafety First\u003c\/strong\u003e — Disconnect power at the breaker and verify zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the control panel cover.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph all primary and secondary wire connections before disconnecting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Disconnect the line-voltage primary and 24V secondary leads, then unbolt the old transformer from the bracket.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new transformer, reconnect primary and secondary leads exactly per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power and confirm 24VAC across the secondary terminals.\u003c\/li\u003e\n\u003c\/ol\u003e\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eNo 24V control power and a dead thermostat display\u003c\/li\u003e\n\u003cli\u003eRepeatedly blown low-voltage fuse or tripped control circuit\u003c\/li\u003e\n\u003cli\u003eAudible buzzing or overheating at the transformer body\u003c\/li\u003e\n\u003cli\u003eRelays and contactor fail to energize despite a call for cooling\/heating\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\u003cp\u003eShips same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.\u003c\/p\u003e","brand":"ICP","offers":[{"title":"Direct Replacement","offer_id":63027289784691,"sku":"1183814-GEN","price":34.0,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63047945486707,"sku":"1183814","price":44.2,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-1183814_018bfe9f-48d3-48a6-9b4b-856b05ef0b97.jpg?v=1782881903","url":"https:\/\/nationalhvacparts.com\/products\/icp-24v-transformer-for-rgs243hrfa0aaaa-40va-control-power-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}