{"product_id":"carrier-factory-authorized-parts-hh18ha199-oem-limit-switch-furnace-temperature-safety-control-replacement","title":"Carrier Factory Authorized Parts HH18HA199 OEM Limit Switch – Furnace Temperature Safety Control Replacement","description":"\u003cp class=\"MsoNormal\"\u003eThe Carrier Factory Authorized Parts HH18HA199 is a genuine OEM limit switch designed for compatible Carrier heating equipment requiring this specific manufacturer part number.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eThe HH18HA199 Limit Switch is a temperature-sensitive electrical safety component used in approved furnace applications. Limit switches help protect heating equipment from excessive temperatures by changing the state of an electrical safety circuit when a specified temperature threshold is reached.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eDesigned as an equipment-specific replacement, the Carrier HH18HA199 helps maintain the manufacturer's intended furnace temperature protection and control operation when properly installed.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eThis OEM replacement component is suitable for professional HVAC service, furnace maintenance, and repair of compatible heating systems.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eKey Features \u0026amp; Function\u003c\/b\u003e\u003c\/p\u003e\n\u003cul style=\"margin-top: 0in;\" type=\"disc\"\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo1; tab-stops: list .5in;\"\u003eBrand: Carrier Factory Authorized Parts\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo1; tab-stops: list .5in;\"\u003eManufacturer Part Number: HH18HA199\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo1; tab-stops: list .5in;\"\u003eOEM Description: Limit Switch\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo1; tab-stops: list .5in;\"\u003eGenuine Carrier OEM replacement component\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo1; tab-stops: list .5in;\"\u003eTemperature-actuated electrical safety control\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo1; tab-stops: list .5in;\"\u003eSupports furnace overtemperature protection\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo1; tab-stops: list .5in;\"\u003eDesigned for compatible Carrier heating equipment\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo1; tab-stops: list .5in;\"\u003eEquipment-specific electrical connections\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo1; tab-stops: list .5in;\"\u003eFactory replacement for approved applications\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo1; tab-stops: list .5in;\"\u003eIntended for professional HVAC maintenance and repair\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eProduct Details \u0026amp; Specifications\u003c\/b\u003e\u003c\/p\u003e\n\u003ctable class=\"MsoNormalTable\" border=\"0\" cellpadding=\"0\" style=\"mso-cellspacing: 1.5pt; mso-yfti-tbllook: 1184;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"mso-yfti-irow: 0; mso-yfti-firstrow: yes;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eSpecification\u003c\/b\u003e\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eDetails\u003c\/b\u003e\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 1;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eManufacturer\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eCarrier\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 2;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eBrand\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eFactory Authorized Parts\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 3;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eManufacturer Part Number\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eHH18HA199\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 4;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eItem Number\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eHH18HA199\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 5;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eOEM Description\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eLimit Switch\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 6;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eProduct Type\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eHVAC Temperature Limit Switch\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 7;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eComponent Category\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eFurnace Temperature \u0026amp; Safety Controls\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 8;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003ePrimary Function\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eTemperature-Activated Safety Switching\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 9;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eEquipment Application\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eCompatible Heating Equipment\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 10;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eOpening Temperature\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eVerify manufacturer specifications\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 11;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eClosing Temperature\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eVerify manufacturer specifications\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 12;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eTemperature Differential\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eVerify manufacturer specifications\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 13;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eReset Type\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eVerify manufacturer specifications\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 14;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eContact Configuration\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eVerify manufacturer specifications\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 15;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eElectrical Rating\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eVerify manufacturer specifications\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 16;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eTerminal Configuration\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eVerify original component\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 17;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eMounting Configuration\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eEquipment-specific\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 18;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eReplacement Type\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eOEM Factory Replacement\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"mso-yfti-irow: 19; mso-yfti-lastrow: yes;\"\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eInstallation\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: .75pt .75pt .75pt .75pt;\"\u003e\n\u003cp class=\"MsoNormal\"\u003eQualified HVAC Technician Recommended\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp class=\"MsoNormal\"\u003eSpecification Note: The exact opening temperature, closing temperature, reset characteristics, and electrical ratings for HH18HA199 have not been independently verified. These specifications should be confirmed using Carrier's manufacturer documentation.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eHVAC Depot Pro Tip\u003c\/b\u003e\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eA furnace limit switch that repeatedly opens may indicate an overheating condition rather than a defective switch.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eBefore replacing the Carrier HH18HA199, inspect the furnace for airflow restrictions, blower problems, or other conditions that may cause excessive operating temperatures.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eRecommended diagnostic checks:\u003c\/p\u003e\n\u003col style=\"margin-top: 0in;\" start=\"1\" type=\"1\"\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l1 level1 lfo2; tab-stops: list .5in;\"\u003eConfirm the furnace model and serial number.\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l1 level1 lfo2; tab-stops: list .5in;\"\u003eVerify the original limit switch part number is HH18HA199.\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l1 level1 lfo2; tab-stops: list .5in;\"\u003eInspect the air filter for excessive dirt or restriction.\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l1 level1 lfo2; tab-stops: list .5in;\"\u003eCheck supply and return airflow.\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l1 level1 lfo2; tab-stops: list .5in;\"\u003eVerify proper blower motor operation.\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l1 level1 lfo2; tab-stops: list .5in;\"\u003eInspect the switch terminals and wiring connections.\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l1 level1 lfo2; tab-stops: list .5in;\"\u003eTest the switch according to manufacturer instructions.\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l1 level1 lfo2; tab-stops: list .5in;\"\u003eConfirm the replacement matches the original temperature ratings.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp class=\"MsoNormal\"\u003eHVAC Depot Pro Tip: Never install a limit switch with a higher temperature rating to prevent repeated furnace shutdowns. The original safety temperature rating must be maintained.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eImportant: Never bypass or jumper a furnace limit switch. Disconnect electrical power before servicing, and correct the underlying cause of overheating before returning equipment to operation.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eEquipment \/ Model Compatibility\u003c\/b\u003e\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eThe Carrier HH18HA199 is intended for select Carrier heating equipment requiring this specific OEM limit switch.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eIt may also be used in Bryant or Payne equipment where the manufacturer explicitly specifies HH18HA199.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eExact compatible equipment models have not been independently verified.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eBefore ordering, confirm:\u003c\/p\u003e\n\u003cul style=\"margin-top: 0in;\" type=\"disc\"\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l0 level1 lfo3; tab-stops: list .5in;\"\u003eComplete equipment model number\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l0 level1 lfo3; tab-stops: list .5in;\"\u003eEquipment serial number\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l0 level1 lfo3; tab-stops: list .5in;\"\u003eOriginal limit switch part number\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l0 level1 lfo3; tab-stops: list .5in;\"\u003eRequired opening and closing temperatures\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l0 level1 lfo3; tab-stops: list .5in;\"\u003eReset type\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l0 level1 lfo3; tab-stops: list .5in;\"\u003eElectrical terminal configuration\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l0 level1 lfo3; tab-stops: list .5in;\"\u003eMounting dimensions and design\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"MsoNormal\"\u003eCompatibility Notice: HH18HA199 is not a universal furnace limit switch. Manufacturer-approved compatibility must be verified before purchasing.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003e \u003c\/p\u003e","brand":"Carrier","offers":[{"title":"Default Title","offer_id":54146630156651,"sku":"662441218781","price":195.89,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0922\/9683\/9531\/files\/HH18HA199.jpg?v=1792511690","url":"https:\/\/tophvacparts.com\/products\/carrier-factory-authorized-parts-hh18ha199-oem-limit-switch-furnace-temperature-safety-control-replacement","provider":"HVAC Parts and Equipment Depot Open To Homeowners and Contractors","version":"1.0","type":"link"}