{"product_id":"tempstar-40va-transformer-for-thb07r34rta-277v-to-24v-ships-today","title":"Tempstar 40VA Transformer for THB07R34RTA — 277V to 24V | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis genuine OEM 40VA control transformer (part 1091226) steps 277V line power down to 24V to energize the low-voltage control circuit on the Tempstar THB07R34RTA packaged terminal air conditioner. The transformer feeds the thermostat, relays, and contactor coils that operate the unit; without a healthy 24V output, the controls go dead and the unit will not run. This listing also covers the unit's companion relays — the 24V relay (1053004) and the 24V DPST relay (1060940) — which switch the compressor and fan loads on command from the control circuit. A failed transformer typically results from a shorted load, age, or a power surge, and is one of the first components to check when a PTAC unit is completely unresponsive but has line voltage present.\u003c\/p\u003e\n\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\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\u003ePart Number\u003c\/td\u003e\n\u003ctd\u003e1091226 (transformer)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompanion Relays\u003c\/td\u003e\n\u003ctd\u003e1053004 (24V), 1060940 (24V DPST)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType\u003c\/td\u003e\n\u003ctd\u003eStep-down control transformer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eTempstar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Voltage\u003c\/td\u003e\n\u003ctd\u003e277V\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\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cp\u003eDesigned as a direct-fit replacement for the 277V Tempstar THB07R34RTA PTAC chassis. Equivalent ICP, Heil, and Comfortmaker THB-series 277V packaged terminal units share this control platform and use the same 40VA transformer and relay hardware. Confirm your line voltage is 277V and match the part number before ordering.\u003c\/p\u003e\n\n\u003ch3\u003eInstallation Guide\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eSafety First\u003c\/strong\u003e — Disconnect power at the breaker and verify zero voltage with a multimeter; 277V is lethal.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the front grille and control-panel cover to expose the transformer and relays.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph the primary and secondary wiring before disconnecting any leads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Unbolt the transformer mounting bracket and disconnect the primary (277V) and secondary (24V) leads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new transformer, wire the 277V primary and 24V secondary per your photo, and confirm tight connections.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power and verify 24V across the secondary, then confirm the unit's controls and relays energize.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eNo 24V output measured on the secondary terminals\u003c\/li\u003e\n\u003cli\u003eUnit completely unresponsive despite confirmed 277V line voltage\u003c\/li\u003e\n\u003cli\u003eBurnt smell, discoloration, or a blown inline control fuse\u003c\/li\u003e\n\u003cli\u003eBuzzing transformer or relays that fail to pull in\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\n\u003cp\u003eShips same day on orders placed before 3 PM CST. 30-day returns on unused parts. Backed by the National HVAC Parts fitment guarantee.\u003c\/p\u003e","brand":"Tempstar","offers":[{"title":"Direct Replacement","offer_id":63021638844787,"sku":"1053004-GEN","price":39.0,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048412397939,"sku":"1053004","price":50.7,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-1053004_153e2436-358d-41c5-bd8e-1e0bd7b47a8e.jpg?v=1782958593","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-40va-transformer-for-thb07r34rta-277v-to-24v-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}