{"product_id":"oem-lennox-start-capacitor-21j29","title":"OEM Lennox Start Capacitor — 21J29","description":"\u003cp\u003eThe genuine OEM Lennox \u003cstrong\u003e21J29\u003c\/strong\u003e start capacitor delivers the high-torque burst of energy needed to get your compressor or motor spinning at startup. Wired into the motor's start winding, it provides the phase shift required to overcome initial inertia, then drops out of the circuit once the motor reaches running speed. This part is engineered to the exact microfarad and voltage ratings specified for your Lennox equipment, ensuring reliable startups season after season.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCommon failure symptoms:\u003c\/strong\u003e When the \u003cstrong\u003e21J29\u003c\/strong\u003e weakens or fails, you'll often hear a humming or clicking sound as the motor struggles to start, notice the unit tripping the breaker, or find the compressor won't turn on at all. A bulged, leaking, or swollen capacitor case is a clear sign it needs replacement. Hard starts and short-cycling also point to a failing start capacitor.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy OEM matters:\u003c\/strong\u003e Lennox systems are calibrated to precise electrical specifications. Installing the factory \u003cstrong\u003e21J29\u003c\/strong\u003e guarantees the correct capacitance and voltage tolerance, protecting your compressor from damaging power draw and preventing premature motor wear. Generic substitutes risk mismatched ratings that shorten equipment life and void coverage. Choose the OEM part for a direct fit and rated performance.\u003c\/p\u003e","brand":"Lennox","offers":[{"title":"Default Title","offer_id":63081112863091,"sku":"LNX-21J29","price":18.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-capacitor-start-LNX-21J29.jpg?v=1783763742","url":"https:\/\/nationalhvacparts.com\/products\/oem-lennox-start-capacitor-21j29","provider":"National HVAC Parts","version":"1.0","type":"link"}