{"product_id":"tempstar-low-pressure-switch-assembly-for-t4h424gkd100-refrigerant-safety-switch-ships-today","title":"Tempstar Low Pressure Switch Assembly for T4H424GKD100 — Refrigerant Safety Switch | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis OEM low pressure switch assembly (part number 1177594) is the refrigerant-side safety control on your Tempstar T4H424GKD100 heat pump. Wired into the 24V control circuit, it continuously monitors suction-line pressure and opens to shut the compressor down if pressure drops below a safe threshold — protecting the compressor from running on a low or lost charge, a blocked metering device, or a frozen evaporator. Without a working low pressure switch, a slow refrigerant leak can let the compressor run dry and self-destruct. The switch is a sealed assembly that mounts on the suction line; over time the contacts can stick open (preventing the unit from ever starting) or weld closed (defeating the protection it's there to provide). It is an inexpensive part that guards a very expensive compressor.\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\u003e1177594\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType\u003c\/td\u003e\n\u003ctd\u003eLow Pressure Switch Assembly (Loss-of-Charge)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eTempstar (ICP \/ Heil)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eControl Voltage\u003c\/td\u003e\n\u003ctd\u003e24V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFunction\u003c\/td\u003e\n\u003ctd\u003eSuction-side compressor protection\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFitment\u003c\/td\u003e\n\u003ctd\u003eOEM 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\u003eFactory-specified for the Tempstar T4H424GKD100 heat pump and shared across matching ICP-family outdoor units (Heil, Comfortmaker, Arcoaire). Confirm the cut-out\/cut-in pressure settings and the connection fitting match your original switch before installing.\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 disconnect and breaker, then verify zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the service panel and locate the pressure switch on the suction (low-side) refrigerant line.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph the two control wires and the switch's mounting position.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Disconnect the 24V leads; if the switch threads onto a Schrader-style port it can be replaced without recovering charge, otherwise recover refrigerant per EPA rules before opening the line.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Thread on the new switch (replace the port core\/seal if required), then reconnect the control leads per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, confirm the switch is closed at normal pressure, and verify the compressor starts and runs.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eCompressor won't start even though charge and pressures are normal (switch stuck open).\u003c\/li\u003e\n\u003cli\u003eUnit short-cycles or nuisance-trips on the low pressure circuit.\u003c\/li\u003e\n\u003cli\u003eNo loss-of-charge protection — compressor runs on a low charge.\u003c\/li\u003e\n\u003cli\u003eCorroded terminals or refrigerant weeping at the switch body.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\n\u003cp\u003eShips same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.\u003c\/p\u003e","brand":"Tempstar","offers":[{"title":"Direct Replacement","offer_id":63021787644275,"sku":"1177594-GEN","price":38.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048463679859,"sku":"1177594","price":50.64,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-pressure-switch-single-1177594_0de31f01-5753-4236-9012-8aaadd0630f2.jpg?v=1782960513","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-low-pressure-switch-assembly-for-t4h424gkd100-refrigerant-safety-switch-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}