{"product_id":"oem-goodman-piston-flowrator-kit-for-asz130181ae-b1789851","title":"OEM Goodman Piston \/ Flowrator Kit for ASZ130181AE — B1789851","description":"\u003ch2\u003eGoodman B1789851 Piston Kit\u003c\/h2\u003e\u003cp\u003eThe Goodman \u003cstrong\u003eB1789851\u003c\/strong\u003e is a factory-original refrigerant metering piston (flowrator) kit for the \u003cstrong\u003eASZ130181AE\u003c\/strong\u003e 13 SEER, 1.5-ton heat pump. The piston is a fixed-orifice metering device that controls refrigerant flow into the coil, setting the system's superheat and subcooling. The precise orifice bore is matched to the unit's tonnage and refrigerant — even a small deviation changes capacity and efficiency, so using the exact factory piston is essential for correct operation.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eOEM Part Number: B1789851\u003c\/li\u003e\n\u003cli\u003eFits: Goodman ASZ130181AE heat pump\u003c\/li\u003e\n\u003cli\u003eType: Fixed-orifice piston \/ flowrator metering device\u003c\/li\u003e\n\u003cli\u003eFunction: Meters refrigerant into the coil at the correct rate\u003c\/li\u003e\n\u003cli\u003eIncludes: Piston (installs into existing flowrator body)\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eOEM vs. Generic\u003c\/h3\u003e\u003cp\u003eThe genuine Goodman piston is bored to the exact orifice size the ASZ13 was engineered around. An incorrect bore — even one size off — causes flooding or starvation, poor capacity, high energy use, and possible compressor damage. Because the part is inexpensive and its orifice is capacity-critical, OEM is the only reliable choice.\u003c\/p\u003e\u003ch3\u003eInstallation Difficulty\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eAdvanced (5\/5).\u003c\/strong\u003e The piston sits inside the sealed refrigerant circuit at the flowrator body. Replacement requires refrigerant recovery, opening the flowrator, seating the correct piston, and evacuating\/recharging the system. EPA Section 608 certification required.\u003c\/p\u003e\u003cp\u003e\u003cem\u003eThis is a sealed-system component — installation must be performed by an EPA-certified HVAC technician using proper recovery and charging equipment.\u003c\/em\u003e\u003c\/p\u003e","brand":"Goodman","offers":[{"title":"Default Title","offer_id":63058303975795,"sku":"GOODMAN-B1789851","price":5.95,"currency_code":"USD","in_stock":true}],"url":"https:\/\/nationalhvacparts.com\/products\/oem-goodman-piston-flowrator-kit-for-asz130181ae-b1789851","provider":"National HVAC Parts","version":"1.0","type":"link"}