{"product_id":"pentairwaterpoolandspainc_473999z","title":"Pentair Thermostatic Expansion Valve | UltraTemp Heat Pump 120HC, 110 | 473999Z","description":"\u003cp\u003eThe Pentair Thermostatic Expansion Valve (473999Z) is the OEM replacement expansion valve for the Pentair UltraTemp Heat Pump Series, specifically the 120HC and 110 models.\u003c\/p\u003e\n\n\u003cp style=\"background-color: #fff3cd; border: 2px solid #FFEAA7; padding: 15px; border-radius: 5px; margin: 15px 0; color: #856404;\"\u003e\n\u003cstrong\u003e⚠️ IMPORTANT: HEAT PUMP REFRIGERANT COMPONENT — PROFESSIONAL SERVICE REQUIRED\u003c\/strong\u003e\u003cbr\u003e\nGas and electrical heater components must be serviced by a licensed pool professional or qualified HVAC technician. Do not attempt to service gas or high-voltage components without proper certification. Thermostatic expansion valves are refrigerant-circuit components — handling refrigerants requires EPA Section 608 certification.\n\u003c\/p\u003e\n\n\u003cp\u003eThe thermostatic expansion valve (TXV) regulates refrigerant flow into the evaporator coil, metering the precise volume required to maintain efficient heat transfer across the refrigerant cycle. A failed or out-of-calibration TXV causes the heat pump to lose heating capacity, short-cycle, or fail to reach target water temperature. Replacing with the correct OEM valve restores the refrigerant circuit to factory specification.\u003c\/p\u003e\n\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; margin: 20px 0; border: 1px solid #ccc;\"\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003ePentair Part Number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e473999Z\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003ePart Name\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eThermostatic Expansion Valve\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eQuantity Included\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eEach\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eFits Into\u003c\/h3\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; margin: 20px 0; border: 1px solid #ccc;\"\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eBrand\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eEquipment Line\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eModel \/ Part Number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eNotes\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003ePentair\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eUltraTemp Heat Pump — UltraTemp Series\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e120HC\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eModel 120HC, 110\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003ePentair\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eUltraTemp Heat Pump — UltraTemp Series\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e110\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eModel 120HC, 110\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003cp\u003e\u003cem\u003eCompatibility is based on Pentair parts documentation and available OEM records. This is not an exhaustive list. For certainty, verify the part number in your equipment's manual or on the original part itself before ordering.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch3\u003ePro Tip\u003c\/h3\u003e\n\u003cp\u003eBefore ordering, confirm the part number stamped or labeled on your existing expansion valve matches 473999Z. TXV capacity and pressure ratings are matched to the specific refrigerant circuit design of each heat pump model — substituting an incorrectly rated valve will result in poor heating performance or compressor damage. This replacement must be installed by a certified HVAC or refrigeration technician with EPA Section 608 certification, as the refrigerant circuit must be recovered, evacuated, and recharged during the repair.\u003c\/p\u003e\n\n\u003c!-- wft:processed:manual:2026-04-06 --\u003e","brand":"Pentair","offers":[{"title":"Default Title","offer_id":53971937001747,"sku":"473999Z","price":256.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0920\/0687\/5411\/files\/pentair-thermostatic-expansion-valve-ultratemp-heat-pump-120hc-110-473999z-7.webp?v=1789672783","url":"https:\/\/poolaroo.com\/products\/pentairwaterpoolandspainc_473999z","provider":"Poolaroo","version":"1.0","type":"link"}